chrome/browser/themes/browser_theme_pack.cc

   1 // Copyright (c) 2012 The Chromium Authors. All rights reserved.
   2 // Use of this source code is governed by a BSD-style license that can be
   3 // found in the LICENSE file.
   4
   5 #include "chrome/browser/themes/browser_theme_pack.h"
   6
   7 #include <limits>
   8
   9 #include "base/files/file.h"
  10 #include "base/memory/ref_counted_memory.h"
  11 #include "base/memory/scoped_ptr.h"
  12 #include "base/stl_util.h"
  13 #include "base/strings/string_number_conversions.h"
  14 #include "base/strings/string_util.h"
  15 #include "base/strings/utf_string_conversions.h"
  16 #include "base/threading/sequenced_worker_pool.h"
  17 #include "base/threading/thread_restrictions.h"
  18 #include "base/values.h"
  19 #include "chrome/browser/themes/theme_properties.h"
  20 #include "chrome/common/extensions/manifest_handlers/theme_handler.h"
  21 #include "content/public/browser/browser_thread.h"
  22 #include "extensions/common/id_util.h"
  23 #include "grit/theme_resources.h"
  24 #include "grit/ui_resources.h"
  25 #include "third_party/skia/include/core/SkCanvas.h"
  26 #include "ui/base/resource/data_pack.h"
  27 #include "ui/base/resource/resource_bundle.h"
  28 #include "ui/gfx/canvas.h"
  29 #include "ui/gfx/codec/png_codec.h"
  30 #include "ui/gfx/image/canvas_image_source.h"
  31 #include "ui/gfx/image/image.h"
  32 #include "ui/gfx/image/image_skia.h"
  33 #include "ui/gfx/image/image_skia_operations.h"
  34 #include "ui/gfx/screen.h"
  35 #include "ui/gfx/size_conversions.h"
  36 #include "ui/gfx/skia_util.h"
  37
  38 using content::BrowserThread;
  39 using extensions::Extension;
  40
  41 namespace {
  42
  43 // Version number of the current theme pack. We just throw out and rebuild
  44 // theme packs that aren't int-equal to this. Increment this number if you
  45 // change default theme assets.
  46 const int kThemePackVersion = 33;
  47
  48 // IDs that are in the DataPack won't clash with the positive integer
  49 // uint16. kHeaderID should always have the maximum value because we want the
  50 // "header" to be written last. That way we can detect whether the pack was
  51 // successfully written and ignore and regenerate if it was only partially
  52 // written (i.e. chrome crashed on a different thread while writing the pack).
  53 const int kMaxID = 0x0000FFFF;  // Max unsigned 16-bit int.
  54 const int kHeaderID = kMaxID - 1;
  55 const int kTintsID = kMaxID - 2;
  56 const int kColorsID = kMaxID - 3;
  57 const int kDisplayPropertiesID = kMaxID - 4;
  58 const int kSourceImagesID = kMaxID - 5;
  59 const int kScaleFactorsID = kMaxID - 6;
  60
  61 // The sum of kFrameBorderThickness and kNonClientRestoredExtraThickness from
  62 // OpaqueBrowserFrameView.
  63 const int kRestoredTabVerticalOffset = 15;
  64
  65 // Persistent constants for the main images that we need. These have the same
  66 // names as their IDR_* counterparts but these values will always stay the
  67 // same.
  68 const int PRS_THEME_FRAME = 1;
  69 const int PRS_THEME_FRAME_INACTIVE = 2;
  70 const int PRS_THEME_FRAME_INCOGNITO = 3;
  71 const int PRS_THEME_FRAME_INCOGNITO_INACTIVE = 4;
  72 const int PRS_THEME_TOOLBAR = 5;
  73 const int PRS_THEME_TAB_BACKGROUND = 6;
  74 const int PRS_THEME_TAB_BACKGROUND_INCOGNITO = 7;
  75 const int PRS_THEME_TAB_BACKGROUND_V = 8;
  76 const int PRS_THEME_NTP_BACKGROUND = 9;
  77 const int PRS_THEME_FRAME_OVERLAY = 10;
  78 const int PRS_THEME_FRAME_OVERLAY_INACTIVE = 11;
  79 const int PRS_THEME_BUTTON_BACKGROUND = 12;
  80 const int PRS_THEME_NTP_ATTRIBUTION = 13;
  81 const int PRS_THEME_WINDOW_CONTROL_BACKGROUND = 14;
  82
  83 struct PersistingImagesTable {
  84   // A non-changing integer ID meant to be saved in theme packs. This ID must
  85   // not change between versions of chrome.
  86   int persistent_id;
  87
  88   // The IDR that depends on the whims of GRIT and therefore changes whenever
  89   // someone adds a new resource.
  90   int idr_id;
  91
  92   // String to check for when parsing theme manifests or NULL if this isn't
  93   // supposed to be changeable by the user.
  94   const char* key;
  95 };
  96
  97 // IDR_* resource names change whenever new resources are added; use persistent
  98 // IDs when storing to a cached pack.
  99 PersistingImagesTable kPersistingImages[] = {
 100   { PRS_THEME_FRAME, IDR_THEME_FRAME,
 101     "theme_frame" },
 102   { PRS_THEME_FRAME_INACTIVE, IDR_THEME_FRAME_INACTIVE,
 103     "theme_frame_inactive" },
 104   { PRS_THEME_FRAME_INCOGNITO, IDR_THEME_FRAME_INCOGNITO,
 105     "theme_frame_incognito" },
 106   { PRS_THEME_FRAME_INCOGNITO_INACTIVE, IDR_THEME_FRAME_INCOGNITO_INACTIVE,
 107     "theme_frame_incognito_inactive" },
 108   { PRS_THEME_TOOLBAR, IDR_THEME_TOOLBAR,
 109     "theme_toolbar" },
 110   { PRS_THEME_TAB_BACKGROUND, IDR_THEME_TAB_BACKGROUND,
 111     "theme_tab_background" },
 112   { PRS_THEME_TAB_BACKGROUND_INCOGNITO, IDR_THEME_TAB_BACKGROUND_INCOGNITO,
 113     "theme_tab_background_incognito" },
 114   { PRS_THEME_TAB_BACKGROUND_V, IDR_THEME_TAB_BACKGROUND_V,
 115     "theme_tab_background_v"},
 116   { PRS_THEME_NTP_BACKGROUND, IDR_THEME_NTP_BACKGROUND,
 117     "theme_ntp_background" },
 118   { PRS_THEME_FRAME_OVERLAY, IDR_THEME_FRAME_OVERLAY,
 119     "theme_frame_overlay" },
 120   { PRS_THEME_FRAME_OVERLAY_INACTIVE, IDR_THEME_FRAME_OVERLAY_INACTIVE,
 121     "theme_frame_overlay_inactive" },
 122   { PRS_THEME_BUTTON_BACKGROUND, IDR_THEME_BUTTON_BACKGROUND,
 123     "theme_button_background" },
 124   { PRS_THEME_NTP_ATTRIBUTION, IDR_THEME_NTP_ATTRIBUTION,
 125     "theme_ntp_attribution" },
 126   { PRS_THEME_WINDOW_CONTROL_BACKGROUND, IDR_THEME_WINDOW_CONTROL_BACKGROUND,
 127     "theme_window_control_background"},
 128
 129   // The rest of these entries have no key because they can't be overridden
 130   // from the json manifest.
 131   { 15, IDR_BACK, NULL },
 132   { 16, IDR_BACK_D, NULL },
 133   { 17, IDR_BACK_H, NULL },
 134   { 18, IDR_BACK_P, NULL },
 135   { 19, IDR_FORWARD, NULL },
 136   { 20, IDR_FORWARD_D, NULL },
 137   { 21, IDR_FORWARD_H, NULL },
 138   { 22, IDR_FORWARD_P, NULL },
 139   { 23, IDR_HOME, NULL },
 140   { 24, IDR_HOME_H, NULL },
 141   { 25, IDR_HOME_P, NULL },
 142   { 26, IDR_RELOAD, NULL },
 143   { 27, IDR_RELOAD_H, NULL },
 144   { 28, IDR_RELOAD_P, NULL },
 145   { 29, IDR_STOP, NULL },
 146   { 30, IDR_STOP_D, NULL },
 147   { 31, IDR_STOP_H, NULL },
 148   { 32, IDR_STOP_P, NULL },
 149   { 33, IDR_BROWSER_ACTIONS_OVERFLOW, NULL },
 150   { 34, IDR_BROWSER_ACTIONS_OVERFLOW_H, NULL },
 151   { 35, IDR_BROWSER_ACTIONS_OVERFLOW_P, NULL },
 152   { 36, IDR_TOOLS, NULL },
 153   { 37, IDR_TOOLS_H, NULL },
 154   { 38, IDR_TOOLS_P, NULL },
 155   { 39, IDR_MENU_DROPARROW, NULL },
 156   { 40, IDR_THROBBER, NULL },
 157   { 41, IDR_THROBBER_WAITING, NULL },
 158   { 42, IDR_THROBBER_LIGHT, NULL },
 159   { 43, IDR_TOOLBAR_BEZEL_HOVER, NULL },
 160   { 44, IDR_TOOLBAR_BEZEL_PRESSED, NULL },
 161   { 45, IDR_TOOLS_BAR, NULL },
 162 };
 163 const size_t kPersistingImagesLength = arraysize(kPersistingImages);
 164
 165 #if defined(OS_WIN)
 166 // Persistent theme ids for Windows.
 167 const int PRS_THEME_FRAME_WIN = 100;
 168 const int PRS_THEME_FRAME_INACTIVE_WIN = 101;
 169 const int PRS_THEME_FRAME_INCOGNITO_WIN = 102;
 170 const int PRS_THEME_FRAME_INCOGNITO_INACTIVE_WIN = 103;
 171 const int PRS_THEME_TOOLBAR_WIN = 104;
 172 const int PRS_THEME_TAB_BACKGROUND_WIN = 105;
 173 const int PRS_THEME_TAB_BACKGROUND_INCOGNITO_WIN = 106;
 174
 175 // Persistent theme to resource id mapping for Windows AURA.
 176 PersistingImagesTable kPersistingImagesWinDesktopAura[] = {
 177   { PRS_THEME_FRAME_WIN, IDR_THEME_FRAME_WIN,
 178     "theme_frame" },
 179   { PRS_THEME_FRAME_INACTIVE_WIN, IDR_THEME_FRAME_INACTIVE_WIN,
 180     "theme_frame_inactive" },
 181   { PRS_THEME_FRAME_INCOGNITO_WIN, IDR_THEME_FRAME_INCOGNITO_WIN,
 182     "theme_frame_incognito" },
 183   { PRS_THEME_FRAME_INCOGNITO_INACTIVE_WIN,
 184     IDR_THEME_FRAME_INCOGNITO_INACTIVE_WIN,
 185     "theme_frame_incognito_inactive" },
 186   { PRS_THEME_TOOLBAR_WIN, IDR_THEME_TOOLBAR_WIN,
 187     "theme_toolbar" },
 188   { PRS_THEME_TAB_BACKGROUND_WIN, IDR_THEME_TAB_BACKGROUND_WIN,
 189     "theme_tab_background" },
 190   { PRS_THEME_TAB_BACKGROUND_INCOGNITO_WIN,
 191     IDR_THEME_TAB_BACKGROUND_INCOGNITO_WIN,
 192     "theme_tab_background_incognito" },
 193 };
 194 const size_t kPersistingImagesWinDesktopAuraLength =
 195     arraysize(kPersistingImagesWinDesktopAura);
 196 #endif
 197
 198 int GetPersistentIDByNameHelper(const std::string& key,
 199                                 const PersistingImagesTable* image_table,
 200                                 size_t image_table_size) {
 201   for (size_t i = 0; i < image_table_size; ++i) {
 202     if (image_table[i].key != NULL &&
 203         base::strcasecmp(key.c_str(), image_table[i].key) == 0) {
 204       return image_table[i].persistent_id;
 205     }
 206   }
 207   return -1;
 208 }
 209
 210 int GetPersistentIDByName(const std::string& key) {
 211   return GetPersistentIDByNameHelper(key,
 212                                      kPersistingImages,
 213                                      kPersistingImagesLength);
 214 }
 215
 216 int GetPersistentIDByIDR(int idr) {
 217   static std::map<int,int>* lookup_table = new std::map<int,int>();
 218   if (lookup_table->empty()) {
 219     for (size_t i = 0; i < kPersistingImagesLength; ++i) {
 220       int idr = kPersistingImages[i].idr_id;
 221       int prs_id = kPersistingImages[i].persistent_id;
 222       (*lookup_table)[idr] = prs_id;
 223     }
 224 #if defined(OS_WIN)
 225     for (size_t i = 0; i < kPersistingImagesWinDesktopAuraLength; ++i) {
 226       int idr = kPersistingImagesWinDesktopAura[i].idr_id;
 227       int prs_id = kPersistingImagesWinDesktopAura[i].persistent_id;
 228       (*lookup_table)[idr] = prs_id;
 229     }
 230 #endif
 231   }
 232   std::map<int,int>::iterator it = lookup_table->find(idr);
 233   return (it == lookup_table->end()) ? -1 : it->second;
 234 }
 235
 236 // Returns true if the scales in |input| match those in |expected|.
 237 // The order must match as the index is used in determining the raw id.
 238 bool InputScalesValid(const base::StringPiece& input,
 239                       const std::vector<ui::ScaleFactor>& expected) {
 240   size_t scales_size = static_cast<size_t>(input.size() / sizeof(float));
 241   if (scales_size != expected.size())
 242     return false;
 243   scoped_ptr<float[]> scales(new float[scales_size]);
 244   // Do a memcpy to avoid misaligned memory access.
 245   memcpy(scales.get(), input.data(), input.size());
 246   for (size_t index = 0; index < scales_size; ++index) {
 247     if (scales[index] != ui::GetImageScale(expected[index]))
 248       return false;
 249   }
 250   return true;
 251 }
 252
 253 // Returns |scale_factors| as a string to be written to disk.
 254 std::string GetScaleFactorsAsString(
 255     const std::vector<ui::ScaleFactor>& scale_factors) {
 256   scoped_ptr<float[]> scales(new float[scale_factors.size()]);
 257   for (size_t i = 0; i < scale_factors.size(); ++i)
 258     scales[i] = ui::GetImageScale(scale_factors[i]);
 259   std::string out_string = std::string(
 260       reinterpret_cast<const char*>(scales.get()),
 261       scale_factors.size() * sizeof(float));
 262   return out_string;
 263 }
 264
 265 struct StringToIntTable {
 266   const char* key;
 267   ThemeProperties::OverwritableByUserThemeProperty id;
 268 };
 269
 270 // Strings used by themes to identify tints in the JSON.
 271 StringToIntTable kTintTable[] = {
 272   { "buttons", ThemeProperties::TINT_BUTTONS },
 273   { "frame", ThemeProperties::TINT_FRAME },
 274   { "frame_inactive", ThemeProperties::TINT_FRAME_INACTIVE },
 275   { "frame_incognito", ThemeProperties::TINT_FRAME_INCOGNITO },
 276   { "frame_incognito_inactive",
 277     ThemeProperties::TINT_FRAME_INCOGNITO_INACTIVE },
 278   { "background_tab", ThemeProperties::TINT_BACKGROUND_TAB },
 279 };
 280 const size_t kTintTableLength = arraysize(kTintTable);
 281
 282 // Strings used by themes to identify colors in the JSON.
 283 StringToIntTable kColorTable[] = {
 284   { "frame", ThemeProperties::COLOR_FRAME },
 285   { "frame_inactive", ThemeProperties::COLOR_FRAME_INACTIVE },
 286   { "frame_incognito", ThemeProperties::COLOR_FRAME_INCOGNITO },
 287   { "frame_incognito_inactive",
 288     ThemeProperties::COLOR_FRAME_INCOGNITO_INACTIVE },
 289   { "toolbar", ThemeProperties::COLOR_TOOLBAR },
 290   { "tab_text", ThemeProperties::COLOR_TAB_TEXT },
 291   { "tab_background_text", ThemeProperties::COLOR_BACKGROUND_TAB_TEXT },
 292   { "bookmark_text", ThemeProperties::COLOR_BOOKMARK_TEXT },
 293   { "ntp_background", ThemeProperties::COLOR_NTP_BACKGROUND },
 294   { "ntp_text", ThemeProperties::COLOR_NTP_TEXT },
 295   { "ntp_link", ThemeProperties::COLOR_NTP_LINK },
 296   { "ntp_link_underline", ThemeProperties::COLOR_NTP_LINK_UNDERLINE },
 297   { "ntp_header", ThemeProperties::COLOR_NTP_HEADER },
 298   { "ntp_section", ThemeProperties::COLOR_NTP_SECTION },
 299   { "ntp_section_text", ThemeProperties::COLOR_NTP_SECTION_TEXT },
 300   { "ntp_section_link", ThemeProperties::COLOR_NTP_SECTION_LINK },
 301   { "ntp_section_link_underline",
 302     ThemeProperties::COLOR_NTP_SECTION_LINK_UNDERLINE },
 303   { "button_background", ThemeProperties::COLOR_BUTTON_BACKGROUND },
 304 };
 305 const size_t kColorTableLength = arraysize(kColorTable);
 306
 307 // Strings used by themes to identify display properties keys in JSON.
 308 StringToIntTable kDisplayProperties[] = {
 309   { "ntp_background_alignment",
 310     ThemeProperties::NTP_BACKGROUND_ALIGNMENT },
 311   { "ntp_background_repeat", ThemeProperties::NTP_BACKGROUND_TILING },
 312   { "ntp_logo_alternate", ThemeProperties::NTP_LOGO_ALTERNATE },
 313 };
 314 const size_t kDisplayPropertiesSize = arraysize(kDisplayProperties);
 315
 316 int GetIntForString(const std::string& key,
 317                     StringToIntTable* table,
 318                     size_t table_length) {
 319   for (size_t i = 0; i < table_length; ++i) {
 320     if (base::strcasecmp(key.c_str(), table[i].key) == 0) {
 321       return table[i].id;
 322     }
 323   }
 324
 325   return -1;
 326 }
 327
 328 struct IntToIntTable {
 329   int key;
 330   int value;
 331 };
 332
 333 // Mapping used in CreateFrameImages() to associate frame images with the
 334 // tint ID that should maybe be applied to it.
 335 IntToIntTable kFrameTintMap[] = {
 336   { PRS_THEME_FRAME, ThemeProperties::TINT_FRAME },
 337   { PRS_THEME_FRAME_INACTIVE, ThemeProperties::TINT_FRAME_INACTIVE },
 338   { PRS_THEME_FRAME_OVERLAY, ThemeProperties::TINT_FRAME },
 339   { PRS_THEME_FRAME_OVERLAY_INACTIVE,
 340     ThemeProperties::TINT_FRAME_INACTIVE },
 341   { PRS_THEME_FRAME_INCOGNITO, ThemeProperties::TINT_FRAME_INCOGNITO },
 342   { PRS_THEME_FRAME_INCOGNITO_INACTIVE,
 343     ThemeProperties::TINT_FRAME_INCOGNITO_INACTIVE },
 344 #if defined(OS_WIN)
 345   { PRS_THEME_FRAME_WIN, ThemeProperties::TINT_FRAME },
 346   { PRS_THEME_FRAME_INACTIVE_WIN, ThemeProperties::TINT_FRAME_INACTIVE },
 347   { PRS_THEME_FRAME_INCOGNITO_WIN, ThemeProperties::TINT_FRAME_INCOGNITO },
 348   { PRS_THEME_FRAME_INCOGNITO_INACTIVE_WIN,
 349     ThemeProperties::TINT_FRAME_INCOGNITO_INACTIVE },
 350 #endif
 351 };
 352
 353 // Mapping used in GenerateTabBackgroundImages() to associate what frame image
 354 // goes with which tab background.
 355 IntToIntTable kTabBackgroundMap[] = {
 356   { PRS_THEME_TAB_BACKGROUND, PRS_THEME_FRAME },
 357   { PRS_THEME_TAB_BACKGROUND_INCOGNITO, PRS_THEME_FRAME_INCOGNITO },
 358 #if defined(OS_WIN)
 359   { PRS_THEME_TAB_BACKGROUND_WIN, PRS_THEME_FRAME_WIN },
 360   { PRS_THEME_TAB_BACKGROUND_INCOGNITO_WIN, PRS_THEME_FRAME_INCOGNITO_WIN },
 361 #endif
 362 };
 363
 364 struct CropEntry {
 365   int prs_id;
 366
 367   // The maximum useful height of the image at |prs_id|.
 368   int max_height;
 369
 370   // Whether cropping the image at |prs_id| should be skipped on OSes which
 371   // have a frame border to the left and right of the web contents.
 372   // This should be true for images which can be used to decorate the border to
 373   // the left and the right of the web contents.
 374   bool skip_if_frame_border;
 375 };
 376
 377 // The images which should be cropped before being saved to the data pack. The
 378 // maximum heights are meant to be conservative as to give room for the UI to
 379 // change without the maximum heights having to be modified.
 380 // |kThemePackVersion| must be incremented if any of the maximum heights below
 381 // are modified.
 382 struct CropEntry kImagesToCrop[] = {
 383   { PRS_THEME_FRAME, 120, true },
 384   { PRS_THEME_FRAME_INACTIVE, 120, true },
 385   { PRS_THEME_FRAME_INCOGNITO, 120, true },
 386   { PRS_THEME_FRAME_INCOGNITO_INACTIVE, 120, true },
 387   { PRS_THEME_FRAME_OVERLAY, 120, true },
 388   { PRS_THEME_FRAME_OVERLAY_INACTIVE, 120, true },
 389   { PRS_THEME_TOOLBAR, 200, false },
 390   { PRS_THEME_BUTTON_BACKGROUND, 60, false },
 391   { PRS_THEME_WINDOW_CONTROL_BACKGROUND, 50, false },
 392 #if defined(OS_WIN)
 393   { PRS_THEME_TOOLBAR_WIN, 200, false }
 394 #endif
 395 };
 396
 397
 398 // A list of images that don't need tinting or any other modification and can
 399 // be byte-copied directly into the finished DataPack. This should contain the
 400 // persistent IDs for all themeable image IDs that aren't in kFrameTintMap,
 401 // kTabBackgroundMap or kImagesToCrop.
 402 const int kPreloadIDs[] = {
 403   PRS_THEME_NTP_BACKGROUND,
 404   PRS_THEME_NTP_ATTRIBUTION,
 405 };
 406
 407 // Returns true if this OS uses a browser frame which has a non zero width to
 408 // the left and the right of the web contents.
 409 bool HasFrameBorder() {
 410 #if defined(OS_CHROMEOS) || defined(OS_MACOSX)
 411   return false;
 412 #else
 413   return true;
 414 #endif
 415 }
 416
 417 // Returns a piece of memory with the contents of the file |path|.
 418 base::RefCountedMemory* ReadFileData(const base::FilePath& path) {
 419   if (!path.empty()) {
 420     base::File file(path, base::File::FLAG_OPEN | base::File::FLAG_READ);
 421     if (file.IsValid()) {
 422       int64 length = file.GetLength();
 423       if (length > 0 && length < INT_MAX) {
 424         int size = static_cast<int>(length);
 425         std::vector<unsigned char> raw_data;
 426         raw_data.resize(size);
 427         char* data = reinterpret_cast<char*>(&(raw_data.front()));
 428         if (file.ReadAtCurrentPos(data, size) == length)
 429           return base::RefCountedBytes::TakeVector(&raw_data);
 430       }
 431     }
 432   }
 433
 434   return NULL;
 435 }
 436
 437 // Shifts an image's HSL values. The caller is responsible for deleting
 438 // the returned image.
 439 gfx::Image CreateHSLShiftedImage(const gfx::Image& image,
 440                                  const color_utils::HSL& hsl_shift) {
 441   const gfx::ImageSkia* src_image = image.ToImageSkia();
 442   return gfx::Image(gfx::ImageSkiaOperations::CreateHSLShiftedImage(
 443       *src_image, hsl_shift));
 444 }
 445
 446 // Computes a bitmap at one scale from a bitmap at a different scale.
 447 SkBitmap CreateLowQualityResizedBitmap(const SkBitmap& source_bitmap,
 448                                        ui::ScaleFactor source_scale_factor,
 449                                        ui::ScaleFactor desired_scale_factor) {
 450   gfx::Size scaled_size = gfx::ToCeiledSize(
 451       gfx::ScaleSize(gfx::Size(source_bitmap.width(),
 452                                source_bitmap.height()),
 453                      ui::GetImageScale(desired_scale_factor) /
 454                      ui::GetImageScale(source_scale_factor)));
 455   SkBitmap scaled_bitmap;
 456   scaled_bitmap.setConfig(SkBitmap::kARGB_8888_Config,
 457                           scaled_size.width(),
 458                           scaled_size.height());
 459   if (!scaled_bitmap.allocPixels())
 460     SK_CRASH();
 461   scaled_bitmap.eraseARGB(0, 0, 0, 0);
 462   SkCanvas canvas(scaled_bitmap);
 463   SkRect scaled_bounds = RectToSkRect(gfx::Rect(scaled_size));
 464   // Note(oshima): The following scaling code doesn't work with
 465   // a mask image.
 466   canvas.drawBitmapRect(source_bitmap, NULL, scaled_bounds);
 467   return scaled_bitmap;
 468 }
 469
 470 // A ImageSkiaSource that scales 100P image to the target scale factor
 471 // if the ImageSkiaRep for the target scale factor isn't available.
 472 class ThemeImageSource: public gfx::ImageSkiaSource {
 473  public:
 474   explicit ThemeImageSource(const gfx::ImageSkia& source) : source_(source) {
 475   }
 476   virtual ~ThemeImageSource() {}
 477
 478   virtual gfx::ImageSkiaRep GetImageForScale(float scale) OVERRIDE {
 479     if (source_.HasRepresentation(scale))
 480       return source_.GetRepresentation(scale);
 481     const gfx::ImageSkiaRep& rep_100p = source_.GetRepresentation(1.0f);
 482     SkBitmap scaled_bitmap = CreateLowQualityResizedBitmap(
 483         rep_100p.sk_bitmap(),
 484         ui::SCALE_FACTOR_100P,
 485         ui::GetSupportedScaleFactor(scale));
 486     return gfx::ImageSkiaRep(scaled_bitmap, scale);
 487   }
 488
 489  private:
 490   const gfx::ImageSkia source_;
 491
 492   DISALLOW_COPY_AND_ASSIGN(ThemeImageSource);
 493 };
 494
 495 // An ImageSkiaSource that delays decoding PNG data into bitmaps until
 496 // needed. Missing data for a scale factor is computed by scaling data for an
 497 // available scale factor. Computed bitmaps are stored for future look up.
 498 class ThemeImagePngSource : public gfx::ImageSkiaSource {
 499  public:
 500   typedef std::map<ui::ScaleFactor,
 501                    scoped_refptr<base::RefCountedMemory> > PngMap;
 502
 503   explicit ThemeImagePngSource(const PngMap& png_map) : png_map_(png_map) {}
 504
 505   virtual ~ThemeImagePngSource() {}
 506
 507  private:
 508   virtual gfx::ImageSkiaRep GetImageForScale(float scale) OVERRIDE {
 509     ui::ScaleFactor scale_factor = ui::GetSupportedScaleFactor(scale);
 510     // Look up the bitmap for |scale factor| in the bitmap map. If found
 511     // return it.
 512     BitmapMap::const_iterator exact_bitmap_it = bitmap_map_.find(scale_factor);
 513     if (exact_bitmap_it != bitmap_map_.end())
 514       return gfx::ImageSkiaRep(exact_bitmap_it->second, scale);
 515
 516     // Look up the raw PNG data for |scale_factor| in the png map. If found,
 517     // decode it, store the result in the bitmap map and return it.
 518     PngMap::const_iterator exact_png_it = png_map_.find(scale_factor);
 519     if (exact_png_it != png_map_.end()) {
 520       SkBitmap bitmap;
 521       if (!gfx::PNGCodec::Decode(exact_png_it->second->front(),
 522                                  exact_png_it->second->size(),
 523                                  &bitmap)) {
 524         NOTREACHED();
 525         return gfx::ImageSkiaRep();
 526       }
 527       bitmap_map_[scale_factor] = bitmap;
 528       return gfx::ImageSkiaRep(bitmap, scale);
 529     }
 530
 531     // Find an available PNG for another scale factor. We want to use the
 532     // highest available scale factor.
 533     PngMap::const_iterator available_png_it = png_map_.end();
 534     for (PngMap::const_iterator png_it = png_map_.begin();
 535          png_it != png_map_.end(); ++png_it) {
 536       if (available_png_it == png_map_.end() ||
 537           ui::GetImageScale(png_it->first) >
 538           ui::GetImageScale(available_png_it->first)) {
 539         available_png_it = png_it;
 540       }
 541     }
 542     if (available_png_it == png_map_.end())
 543       return gfx::ImageSkiaRep();
 544     ui::ScaleFactor available_scale_factor = available_png_it->first;
 545
 546     // Look up the bitmap for |available_scale_factor| in the bitmap map.
 547     // If not found, decode the corresponging png data, store the result
 548     // in the bitmap map.
 549     BitmapMap::const_iterator available_bitmap_it =
 550         bitmap_map_.find(available_scale_factor);
 551     if (available_bitmap_it == bitmap_map_.end()) {
 552       SkBitmap available_bitmap;
 553       if (!gfx::PNGCodec::Decode(available_png_it->second->front(),
 554                                  available_png_it->second->size(),
 555                                  &available_bitmap)) {
 556         NOTREACHED();
 557         return gfx::ImageSkiaRep();
 558       }
 559       bitmap_map_[available_scale_factor] = available_bitmap;
 560       available_bitmap_it = bitmap_map_.find(available_scale_factor);
 561     }
 562
 563     // Scale the available bitmap to the desired scale factor, store the result
 564     // in the bitmap map and return it.
 565     SkBitmap scaled_bitmap = CreateLowQualityResizedBitmap(
 566         available_bitmap_it->second,
 567         available_scale_factor,
 568         scale_factor);
 569     bitmap_map_[scale_factor] = scaled_bitmap;
 570     return gfx::ImageSkiaRep(scaled_bitmap, scale);
 571   }
 572
 573   PngMap png_map_;
 574
 575   typedef std::map<ui::ScaleFactor, SkBitmap> BitmapMap;
 576   BitmapMap bitmap_map_;
 577
 578   DISALLOW_COPY_AND_ASSIGN(ThemeImagePngSource);
 579 };
 580
 581 class TabBackgroundImageSource: public gfx::CanvasImageSource {
 582  public:
 583   TabBackgroundImageSource(const gfx::ImageSkia& image_to_tint,
 584                            const gfx::ImageSkia& overlay,
 585                            const color_utils::HSL& hsl_shift,
 586                            int vertical_offset)
 587       : gfx::CanvasImageSource(image_to_tint.size(), false),
 588         image_to_tint_(image_to_tint),
 589         overlay_(overlay),
 590         hsl_shift_(hsl_shift),
 591         vertical_offset_(vertical_offset) {
 592   }
 593
 594   virtual ~TabBackgroundImageSource() {
 595   }
 596
 597   // Overridden from CanvasImageSource:
 598   virtual void Draw(gfx::Canvas* canvas) OVERRIDE {
 599     gfx::ImageSkia bg_tint =
 600         gfx::ImageSkiaOperations::CreateHSLShiftedImage(image_to_tint_,
 601             hsl_shift_);
 602     canvas->TileImageInt(bg_tint, 0, vertical_offset_, 0, 0,
 603         size().width(), size().height());
 604
 605     // If they've provided a custom image, overlay it.
 606     if (!overlay_.isNull()) {
 607       canvas->TileImageInt(overlay_, 0, 0, size().width(),
 608                            overlay_.height());
 609     }
 610   }
 611
 612  private:
 613   const gfx::ImageSkia image_to_tint_;
 614   const gfx::ImageSkia overlay_;
 615   const color_utils::HSL hsl_shift_;
 616   const int vertical_offset_;
 617
 618   DISALLOW_COPY_AND_ASSIGN(TabBackgroundImageSource);
 619 };
 620
 621 }  // namespace
 622
 623 BrowserThemePack::~BrowserThemePack() {
 624   if (!data_pack_.get()) {
 625     delete header_;
 626     delete [] tints_;
 627     delete [] colors_;
 628     delete [] display_properties_;
 629     delete [] source_images_;
 630   }
 631 }
 632
 633 // static
 634 scoped_refptr<BrowserThemePack> BrowserThemePack::BuildFromExtension(
 635     const Extension* extension) {
 636   DCHECK(BrowserThread::CurrentlyOn(BrowserThread::UI));
 637   DCHECK(extension);
 638   DCHECK(extension->is_theme());
 639
 640   scoped_refptr<BrowserThemePack> pack(new BrowserThemePack);
 641   pack->BuildHeader(extension);
 642   pack->BuildTintsFromJSON(extensions::ThemeInfo::GetTints(extension));
 643   pack->BuildColorsFromJSON(extensions::ThemeInfo::GetColors(extension));
 644   pack->BuildDisplayPropertiesFromJSON(
 645       extensions::ThemeInfo::GetDisplayProperties(extension));
 646
 647   // Builds the images. (Image building is dependent on tints).
 648   FilePathMap file_paths;
 649   pack->ParseImageNamesFromJSON(
 650       extensions::ThemeInfo::GetImages(extension),
 651       extension->path(),
 652       &file_paths);
 653   pack->BuildSourceImagesArray(file_paths);
 654
 655   if (!pack->LoadRawBitmapsTo(file_paths, &pack->images_on_ui_thread_))
 656     return NULL;
 657
 658   pack->CreateImages(&pack->images_on_ui_thread_);
 659
 660   // Make sure the |images_on_file_thread_| has bitmaps for supported
 661   // scale factors before passing to FILE thread.
 662   pack->images_on_file_thread_ = pack->images_on_ui_thread_;
 663   for (ImageCache::iterator it = pack->images_on_file_thread_.begin();
 664        it != pack->images_on_file_thread_.end(); ++it) {
 665     gfx::ImageSkia* image_skia =
 666         const_cast<gfx::ImageSkia*>(it->second.ToImageSkia());
 667     image_skia->MakeThreadSafe();
 668   }
 669
 670   // Set ThemeImageSource on |images_on_ui_thread_| to resample the source
 671   // image if a caller of BrowserThemePack::GetImageNamed() requests an
 672   // ImageSkiaRep for a scale factor not specified by the theme author.
 673   // Callers of BrowserThemePack::GetImageNamed() to be able to retrieve
 674   // ImageSkiaReps for all supported scale factors.
 675   for (ImageCache::iterator it = pack->images_on_ui_thread_.begin();
 676        it != pack->images_on_ui_thread_.end(); ++it) {
 677     const gfx::ImageSkia source_image_skia = it->second.AsImageSkia();
 678     ThemeImageSource* source = new ThemeImageSource(source_image_skia);
 679     // image_skia takes ownership of source.
 680     gfx::ImageSkia image_skia(source, source_image_skia.size());
 681     it->second = gfx::Image(image_skia);
 682   }
 683
 684   // Generate raw images (for new-tab-page attribution and background) for
 685   // any missing scale from an available scale image.
 686   for (size_t i = 0; i < arraysize(kPreloadIDs); ++i) {
 687     pack->GenerateRawImageForAllSupportedScales(kPreloadIDs[i]);
 688   }
 689
 690   // The BrowserThemePack is now in a consistent state.
 691   return pack;
 692 }
 693
 694 // static
 695 scoped_refptr<BrowserThemePack> BrowserThemePack::BuildFromDataPack(
 696     const base::FilePath& path, const std::string& expected_id) {
 697   DCHECK(BrowserThread::CurrentlyOn(BrowserThread::UI));
 698   // Allow IO on UI thread due to deep-seated theme design issues.
 699   // (see http://crbug.com/80206)
 700   base::ThreadRestrictions::ScopedAllowIO allow_io;
 701   scoped_refptr<BrowserThemePack> pack(new BrowserThemePack);
 702   // Scale factor parameter is moot as data pack has image resources for all
 703   // supported scale factors.
 704   pack->data_pack_.reset(
 705       new ui::DataPack(ui::SCALE_FACTOR_NONE));
 706
 707   if (!pack->data_pack_->LoadFromPath(path)) {
 708     LOG(ERROR) << "Failed to load theme data pack.";
 709     return NULL;
 710   }
 711
 712   base::StringPiece pointer;
 713   if (!pack->data_pack_->GetStringPiece(kHeaderID, &pointer))
 714     return NULL;
 715   pack->header_ = reinterpret_cast<BrowserThemePackHeader*>(const_cast<char*>(
 716       pointer.data()));
 717
 718   if (pack->header_->version != kThemePackVersion) {
 719     DLOG(ERROR) << "BuildFromDataPack failure! Version mismatch!";
 720     return NULL;
 721   }
 722   // TODO(erg): Check endianess once DataPack works on the other endian.
 723   std::string theme_id(reinterpret_cast<char*>(pack->header_->theme_id),
 724                        extensions::id_util::kIdSize);
 725   std::string truncated_id =
 726       expected_id.substr(0, extensions::id_util::kIdSize);
 727   if (theme_id != truncated_id) {
 728     DLOG(ERROR) << "Wrong id: " << theme_id << " vs " << expected_id;
 729     return NULL;
 730   }
 731
 732   if (!pack->data_pack_->GetStringPiece(kTintsID, &pointer))
 733     return NULL;
 734   pack->tints_ = reinterpret_cast<TintEntry*>(const_cast<char*>(
 735       pointer.data()));
 736
 737   if (!pack->data_pack_->GetStringPiece(kColorsID, &pointer))
 738     return NULL;
 739   pack->colors_ =
 740       reinterpret_cast<ColorPair*>(const_cast<char*>(pointer.data()));
 741
 742   if (!pack->data_pack_->GetStringPiece(kDisplayPropertiesID, &pointer))
 743     return NULL;
 744   pack->display_properties_ = reinterpret_cast<DisplayPropertyPair*>(
 745       const_cast<char*>(pointer.data()));
 746
 747   if (!pack->data_pack_->GetStringPiece(kSourceImagesID, &pointer))
 748     return NULL;
 749   pack->source_images_ = reinterpret_cast<int*>(
 750       const_cast<char*>(pointer.data()));
 751
 752   if (!pack->data_pack_->GetStringPiece(kScaleFactorsID, &pointer))
 753     return NULL;
 754
 755   if (!InputScalesValid(pointer, pack->scale_factors_)) {
 756     DLOG(ERROR) << "BuildFromDataPack failure! The pack scale factors differ "
 757                 << "from those supported by platform.";
 758   }
 759   return pack;
 760 }
 761
 762 // static
 763 void BrowserThemePack::GetThemeableImageIDRs(std::set<int>* result) {
 764   if (!result)
 765     return;
 766
 767   result->clear();
 768   for (size_t i = 0; i < kPersistingImagesLength; ++i)
 769     result->insert(kPersistingImages[i].idr_id);
 770
 771 #if defined(OS_WIN)
 772   for (size_t i = 0; i < kPersistingImagesWinDesktopAuraLength; ++i)
 773     result->insert(kPersistingImagesWinDesktopAura[i].idr_id);
 774 #endif
 775 }
 776
 777 bool BrowserThemePack::WriteToDisk(const base::FilePath& path) const {
 778   // Add resources for each of the property arrays.
 779   RawDataForWriting resources;
 780   resources[kHeaderID] = base::StringPiece(
 781       reinterpret_cast<const char*>(header_), sizeof(BrowserThemePackHeader));
 782   resources[kTintsID] = base::StringPiece(
 783       reinterpret_cast<const char*>(tints_),
 784       sizeof(TintEntry[kTintTableLength]));
 785   resources[kColorsID] = base::StringPiece(
 786       reinterpret_cast<const char*>(colors_),
 787       sizeof(ColorPair[kColorTableLength]));
 788   resources[kDisplayPropertiesID] = base::StringPiece(
 789       reinterpret_cast<const char*>(display_properties_),
 790       sizeof(DisplayPropertyPair[kDisplayPropertiesSize]));
 791
 792   int source_count = 1;
 793   int* end = source_images_;
 794   for (; *end != -1 ; end++)
 795     source_count++;
 796   resources[kSourceImagesID] = base::StringPiece(
 797       reinterpret_cast<const char*>(source_images_),
 798       source_count * sizeof(*source_images_));
 799
 800   // Store results of GetScaleFactorsAsString() in std::string as
 801   // base::StringPiece does not copy data in constructor.
 802   std::string scale_factors_string = GetScaleFactorsAsString(scale_factors_);
 803   resources[kScaleFactorsID] = scale_factors_string;
 804
 805   AddRawImagesTo(image_memory_, &resources);
 806
 807   RawImages reencoded_images;
 808   RepackImages(images_on_file_thread_, &reencoded_images);
 809   AddRawImagesTo(reencoded_images, &resources);
 810
 811   return ui::DataPack::WritePack(path, resources, ui::DataPack::BINARY);
 812 }
 813
 814 bool BrowserThemePack::GetTint(int id, color_utils::HSL* hsl) const {
 815   if (tints_) {
 816     for (size_t i = 0; i < kTintTableLength; ++i) {
 817       if (tints_[i].id == id) {
 818         hsl->h = tints_[i].h;
 819         hsl->s = tints_[i].s;
 820         hsl->l = tints_[i].l;
 821         return true;
 822       }
 823     }
 824   }
 825
 826   return false;
 827 }
 828
 829 bool BrowserThemePack::GetColor(int id, SkColor* color) const {
 830   if (colors_) {
 831     for (size_t i = 0; i < kColorTableLength; ++i) {
 832       if (colors_[i].id == id) {
 833         *color = colors_[i].color;
 834         return true;
 835       }
 836     }
 837   }
 838
 839   return false;
 840 }
 841
 842 bool BrowserThemePack::GetDisplayProperty(int id, int* result) const {
 843   if (display_properties_) {
 844     for (size_t i = 0; i < kDisplayPropertiesSize; ++i) {
 845       if (display_properties_[i].id == id) {
 846         *result = display_properties_[i].property;
 847         return true;
 848       }
 849     }
 850   }
 851
 852   return false;
 853 }
 854
 855 gfx::Image BrowserThemePack::GetImageNamed(int idr_id) {
 856   int prs_id = GetPersistentIDByIDR(idr_id);
 857   if (prs_id == -1)
 858     return gfx::Image();
 859
 860   // Check if the image is cached.
 861   ImageCache::const_iterator image_iter = images_on_ui_thread_.find(prs_id);
 862   if (image_iter != images_on_ui_thread_.end())
 863     return image_iter->second;
 864
 865   ThemeImagePngSource::PngMap png_map;
 866   for (size_t i = 0; i < scale_factors_.size(); ++i) {
 867     scoped_refptr<base::RefCountedMemory> memory =
 868         GetRawData(idr_id, scale_factors_[i]);
 869     if (memory.get())
 870       png_map[scale_factors_[i]] = memory;
 871   }
 872   if (!png_map.empty()) {
 873     gfx::ImageSkia image_skia(new ThemeImagePngSource(png_map), 1.0f);
 874     // |image_skia| takes ownership of ThemeImagePngSource.
 875     gfx::Image ret = gfx::Image(image_skia);
 876     images_on_ui_thread_[prs_id] = ret;
 877     return ret;
 878   }
 879
 880   return gfx::Image();
 881 }
 882
 883 base::RefCountedMemory* BrowserThemePack::GetRawData(
 884     int idr_id,
 885     ui::ScaleFactor scale_factor) const {
 886   base::RefCountedMemory* memory = NULL;
 887   int prs_id = GetPersistentIDByIDR(idr_id);
 888   int raw_id = GetRawIDByPersistentID(prs_id, scale_factor);
 889
 890   if (raw_id != -1) {
 891     if (data_pack_.get()) {
 892       memory = data_pack_->GetStaticMemory(raw_id);
 893     } else {
 894       RawImages::const_iterator it = image_memory_.find(raw_id);
 895       if (it != image_memory_.end()) {
 896         memory = it->second.get();
 897       }
 898     }
 899   }
 900
 901   return memory;
 902 }
 903
 904 bool BrowserThemePack::HasCustomImage(int idr_id) const {
 905   int prs_id = GetPersistentIDByIDR(idr_id);
 906   if (prs_id == -1)
 907     return false;
 908
 909   int* img = source_images_;
 910   for (; *img != -1; ++img) {
 911     if (*img == prs_id)
 912       return true;
 913   }
 914
 915   return false;
 916 }
 917
 918 // private:
 919
 920 BrowserThemePack::BrowserThemePack()
 921     : CustomThemeSupplier(EXTENSION),
 922       header_(NULL),
 923       tints_(NULL),
 924       colors_(NULL),
 925       display_properties_(NULL),
 926       source_images_(NULL) {
 927   scale_factors_ = ui::GetSupportedScaleFactors();
 928 }
 929
 930 void BrowserThemePack::BuildHeader(const Extension* extension) {
 931   header_ = new BrowserThemePackHeader;
 932   header_->version = kThemePackVersion;
 933
 934   // TODO(erg): Need to make this endian safe on other computers. Prerequisite
 935   // is that ui::DataPack removes this same check.
 936 #if defined(__BYTE_ORDER)
 937   // Linux check
 938   COMPILE_ASSERT(__BYTE_ORDER == __LITTLE_ENDIAN,
 939                  datapack_assumes_little_endian);
 940 #elif defined(__BIG_ENDIAN__)
 941   // Mac check
 942   #error DataPack assumes little endian
 943 #endif
 944   header_->little_endian = 1;
 945
 946   const std::string& id = extension->id();
 947   memcpy(header_->theme_id, id.c_str(), extensions::id_util::kIdSize);
 948 }
 949
 950 void BrowserThemePack::BuildTintsFromJSON(
 951     const base::DictionaryValue* tints_value) {
 952   tints_ = new TintEntry[kTintTableLength];
 953   for (size_t i = 0; i < kTintTableLength; ++i) {
 954     tints_[i].id = -1;
 955     tints_[i].h = -1;
 956     tints_[i].s = -1;
 957     tints_[i].l = -1;
 958   }
 959
 960   if (!tints_value)
 961     return;
 962
 963   // Parse the incoming data from |tints_value| into an intermediary structure.
 964   std::map<int, color_utils::HSL> temp_tints;
 965   for (base::DictionaryValue::Iterator iter(*tints_value); !iter.IsAtEnd();
 966        iter.Advance()) {
 967     const base::ListValue* tint_list;
 968     if (iter.value().GetAsList(&tint_list) &&
 969         (tint_list->GetSize() == 3)) {
 970       color_utils::HSL hsl = { -1, -1, -1 };
 971
 972       if (tint_list->GetDouble(0, &hsl.h) &&
 973           tint_list->GetDouble(1, &hsl.s) &&
 974           tint_list->GetDouble(2, &hsl.l)) {
 975         int id = GetIntForString(iter.key(), kTintTable, kTintTableLength);
 976         if (id != -1) {
 977           temp_tints[id] = hsl;
 978         }
 979       }
 980     }
 981   }
 982
 983   // Copy data from the intermediary data structure to the array.
 984   size_t count = 0;
 985   for (std::map<int, color_utils::HSL>::const_iterator it =
 986            temp_tints.begin();
 987        it != temp_tints.end() && count < kTintTableLength;
 988        ++it, ++count) {
 989     tints_[count].id = it->first;
 990     tints_[count].h = it->second.h;
 991     tints_[count].s = it->second.s;
 992     tints_[count].l = it->second.l;
 993   }
 994 }
 995
 996 void BrowserThemePack::BuildColorsFromJSON(
 997     const base::DictionaryValue* colors_value) {
 998   colors_ = new ColorPair[kColorTableLength];
 999   for (size_t i = 0; i < kColorTableLength; ++i) {
1000     colors_[i].id = -1;
1001     colors_[i].color = SkColorSetRGB(0, 0, 0);
1002   }
1003
1004   std::map<int, SkColor> temp_colors;
1005   if (colors_value)
1006     ReadColorsFromJSON(colors_value, &temp_colors);
1007   GenerateMissingColors(&temp_colors);
1008
1009   // Copy data from the intermediary data structure to the array.
1010   size_t count = 0;
1011   for (std::map<int, SkColor>::const_iterator it = temp_colors.begin();
1012        it != temp_colors.end() && count < kColorTableLength; ++it, ++count) {
1013     colors_[count].id = it->first;
1014     colors_[count].color = it->second;
1015   }
1016 }
1017
1018 void BrowserThemePack::ReadColorsFromJSON(
1019     const base::DictionaryValue* colors_value,
1020     std::map<int, SkColor>* temp_colors) {
1021   // Parse the incoming data from |colors_value| into an intermediary structure.
1022   for (base::DictionaryValue::Iterator iter(*colors_value); !iter.IsAtEnd();
1023        iter.Advance()) {
1024     const base::ListValue* color_list;
1025     if (iter.value().GetAsList(&color_list) &&
1026         ((color_list->GetSize() == 3) || (color_list->GetSize() == 4))) {
1027       SkColor color = SK_ColorWHITE;
1028       int r, g, b;
1029       if (color_list->GetInteger(0, &r) &&
1030           color_list->GetInteger(1, &g) &&
1031           color_list->GetInteger(2, &b)) {
1032         if (color_list->GetSize() == 4) {
1033           double alpha;
1034           int alpha_int;
1035           if (color_list->GetDouble(3, &alpha)) {
1036             color = SkColorSetARGB(static_cast<int>(alpha * 255), r, g, b);
1037           } else if (color_list->GetInteger(3, &alpha_int) &&
1038                      (alpha_int == 0 || alpha_int == 1)) {
1039             color = SkColorSetARGB(alpha_int ? 255 : 0, r, g, b);
1040           } else {
1041             // Invalid entry for part 4.
1042             continue;
1043           }
1044         } else {
1045           color = SkColorSetRGB(r, g, b);
1046         }
1047
1048         int id = GetIntForString(iter.key(), kColorTable, kColorTableLength);
1049         if (id != -1) {
1050           (*temp_colors)[id] = color;
1051         }
1052       }
1053     }
1054   }
1055 }
1056
1057 void BrowserThemePack::GenerateMissingColors(
1058     std::map<int, SkColor>* colors) {
1059   // Generate link colors, if missing. (See GetColor()).
1060   if (!colors->count(ThemeProperties::COLOR_NTP_HEADER) &&
1061       colors->count(ThemeProperties::COLOR_NTP_SECTION)) {
1062     (*colors)[ThemeProperties::COLOR_NTP_HEADER] =
1063         (*colors)[ThemeProperties::COLOR_NTP_SECTION];
1064   }
1065
1066   if (!colors->count(ThemeProperties::COLOR_NTP_SECTION_LINK_UNDERLINE) &&
1067       colors->count(ThemeProperties::COLOR_NTP_SECTION_LINK)) {
1068     SkColor color_section_link =
1069         (*colors)[ThemeProperties::COLOR_NTP_SECTION_LINK];
1070     (*colors)[ThemeProperties::COLOR_NTP_SECTION_LINK_UNDERLINE] =
1071         SkColorSetA(color_section_link, SkColorGetA(color_section_link) / 3);
1072   }
1073
1074   if (!colors->count(ThemeProperties::COLOR_NTP_LINK_UNDERLINE) &&
1075       colors->count(ThemeProperties::COLOR_NTP_LINK)) {
1076     SkColor color_link = (*colors)[ThemeProperties::COLOR_NTP_LINK];
1077     (*colors)[ThemeProperties::COLOR_NTP_LINK_UNDERLINE] =
1078         SkColorSetA(color_link, SkColorGetA(color_link) / 3);
1079   }
1080
1081   // Generate frame colors, if missing. (See GenerateFrameColors()).
1082   SkColor frame;
1083   std::map<int, SkColor>::const_iterator it =
1084       colors->find(ThemeProperties::COLOR_FRAME);
1085   if (it != colors->end()) {
1086     frame = it->second;
1087   } else {
1088     frame = ThemeProperties::GetDefaultColor(
1089         ThemeProperties::COLOR_FRAME);
1090   }
1091
1092   if (!colors->count(ThemeProperties::COLOR_FRAME)) {
1093     (*colors)[ThemeProperties::COLOR_FRAME] =
1094         HSLShift(frame, GetTintInternal(ThemeProperties::TINT_FRAME));
1095   }
1096   if (!colors->count(ThemeProperties::COLOR_FRAME_INACTIVE)) {
1097     (*colors)[ThemeProperties::COLOR_FRAME_INACTIVE] =
1098         HSLShift(frame, GetTintInternal(
1099             ThemeProperties::TINT_FRAME_INACTIVE));
1100   }
1101   if (!colors->count(ThemeProperties::COLOR_FRAME_INCOGNITO)) {
1102     (*colors)[ThemeProperties::COLOR_FRAME_INCOGNITO] =
1103         HSLShift(frame, GetTintInternal(
1104             ThemeProperties::TINT_FRAME_INCOGNITO));
1105   }
1106   if (!colors->count(ThemeProperties::COLOR_FRAME_INCOGNITO_INACTIVE)) {
1107     (*colors)[ThemeProperties::COLOR_FRAME_INCOGNITO_INACTIVE] =
1108         HSLShift(frame, GetTintInternal(
1109             ThemeProperties::TINT_FRAME_INCOGNITO_INACTIVE));
1110   }
1111 }
1112
1113 void BrowserThemePack::BuildDisplayPropertiesFromJSON(
1114     const base::DictionaryValue* display_properties_value) {
1115   display_properties_ = new DisplayPropertyPair[kDisplayPropertiesSize];
1116   for (size_t i = 0; i < kDisplayPropertiesSize; ++i) {
1117     display_properties_[i].id = -1;
1118     display_properties_[i].property = 0;
1119   }
1120
1121   if (!display_properties_value)
1122     return;
1123
1124   std::map<int, int> temp_properties;
1125   for (base::DictionaryValue::Iterator iter(*display_properties_value);
1126        !iter.IsAtEnd(); iter.Advance()) {
1127     int property_id = GetIntForString(iter.key(), kDisplayProperties,
1128                                       kDisplayPropertiesSize);
1129     switch (property_id) {
1130       case ThemeProperties::NTP_BACKGROUND_ALIGNMENT: {
1131         std::string val;
1132         if (iter.value().GetAsString(&val)) {
1133           temp_properties[ThemeProperties::NTP_BACKGROUND_ALIGNMENT] =
1134               ThemeProperties::StringToAlignment(val);
1135         }
1136         break;
1137       }
1138       case ThemeProperties::NTP_BACKGROUND_TILING: {
1139         std::string val;
1140         if (iter.value().GetAsString(&val)) {
1141           temp_properties[ThemeProperties::NTP_BACKGROUND_TILING] =
1142               ThemeProperties::StringToTiling(val);
1143         }
1144         break;
1145       }
1146       case ThemeProperties::NTP_LOGO_ALTERNATE: {
1147         int val = 0;
1148         if (iter.value().GetAsInteger(&val))
1149           temp_properties[ThemeProperties::NTP_LOGO_ALTERNATE] = val;
1150         break;
1151       }
1152     }
1153   }
1154
1155   // Copy data from the intermediary data structure to the array.
1156   size_t count = 0;
1157   for (std::map<int, int>::const_iterator it = temp_properties.begin();
1158        it != temp_properties.end() && count < kDisplayPropertiesSize;
1159        ++it, ++count) {
1160     display_properties_[count].id = it->first;
1161     display_properties_[count].property = it->second;
1162   }
1163 }
1164
1165 void BrowserThemePack::ParseImageNamesFromJSON(
1166     const base::DictionaryValue* images_value,
1167     const base::FilePath& images_path,
1168     FilePathMap* file_paths) const {
1169   if (!images_value)
1170     return;
1171
1172   for (base::DictionaryValue::Iterator iter(*images_value); !iter.IsAtEnd();
1173        iter.Advance()) {
1174     if (iter.value().IsType(base::Value::TYPE_DICTIONARY)) {
1175       const base::DictionaryValue* inner_value = NULL;
1176       if (iter.value().GetAsDictionary(&inner_value)) {
1177         for (base::DictionaryValue::Iterator inner_iter(*inner_value);
1178              !inner_iter.IsAtEnd();
1179              inner_iter.Advance()) {
1180           std::string name;
1181           ui::ScaleFactor scale_factor = ui::SCALE_FACTOR_NONE;
1182           if (GetScaleFactorFromManifestKey(inner_iter.key(), &scale_factor) &&
1183               inner_iter.value().IsType(base::Value::TYPE_STRING) &&
1184               inner_iter.value().GetAsString(&name)) {
1185             AddFileAtScaleToMap(iter.key(),
1186                                 scale_factor,
1187                                 images_path.AppendASCII(name),
1188                                 file_paths);
1189           }
1190         }
1191       }
1192     } else if (iter.value().IsType(base::Value::TYPE_STRING)) {
1193       std::string name;
1194       if (iter.value().GetAsString(&name)) {
1195         AddFileAtScaleToMap(iter.key(),
1196                             ui::SCALE_FACTOR_100P,
1197                             images_path.AppendASCII(name),
1198                             file_paths);
1199       }
1200     }
1201   }
1202 }
1203
1204 void BrowserThemePack::AddFileAtScaleToMap(const std::string& image_name,
1205                                            ui::ScaleFactor scale_factor,
1206                                            const base::FilePath& image_path,
1207                                            FilePathMap* file_paths) const {
1208   int id = GetPersistentIDByName(image_name);
1209   if (id != -1)
1210     (*file_paths)[id][scale_factor] = image_path;
1211 #if defined(OS_WIN)
1212   id = GetPersistentIDByNameHelper(image_name,
1213                                    kPersistingImagesWinDesktopAura,
1214                                    kPersistingImagesWinDesktopAuraLength);
1215   if (id != -1)
1216     (*file_paths)[id][scale_factor] = image_path;
1217 #endif
1218 }
1219
1220 void BrowserThemePack::BuildSourceImagesArray(const FilePathMap& file_paths) {
1221   std::vector<int> ids;
1222   for (FilePathMap::const_iterator it = file_paths.begin();
1223        it != file_paths.end(); ++it) {
1224     ids.push_back(it->first);
1225   }
1226
1227   source_images_ = new int[ids.size() + 1];
1228   std::copy(ids.begin(), ids.end(), source_images_);
1229   source_images_[ids.size()] = -1;
1230 }
1231
1232 bool BrowserThemePack::LoadRawBitmapsTo(
1233     const FilePathMap& file_paths,
1234     ImageCache* image_cache) {
1235   // Themes should be loaded on the file thread, not the UI thread.
1236   // http://crbug.com/61838
1237   base::ThreadRestrictions::ScopedAllowIO allow_io;
1238
1239   for (FilePathMap::const_iterator it = file_paths.begin();
1240        it != file_paths.end(); ++it) {
1241     int prs_id = it->first;
1242     // Some images need to go directly into |image_memory_|. No modification is
1243     // necessary or desirable.
1244     bool is_copyable = false;
1245     for (size_t i = 0; i < arraysize(kPreloadIDs); ++i) {
1246       if (kPreloadIDs[i] == prs_id) {
1247         is_copyable = true;
1248         break;
1249       }
1250     }
1251     gfx::ImageSkia image_skia;
1252     for (int pass = 0; pass < 2; ++pass) {
1253       // Two passes: In the first pass, we process only scale factor
1254       // 100% and in the second pass all other scale factors. We
1255       // process scale factor 100% first because the first image added
1256       // in image_skia.AddRepresentation() determines the DIP size for
1257       // all representations.
1258       for (ScaleFactorToFileMap::const_iterator s2f = it->second.begin();
1259            s2f != it->second.end(); ++s2f) {
1260         ui::ScaleFactor scale_factor = s2f->first;
1261         if ((pass == 0 && scale_factor != ui::SCALE_FACTOR_100P) ||
1262             (pass == 1 && scale_factor == ui::SCALE_FACTOR_100P)) {
1263           continue;
1264         }
1265         scoped_refptr<base::RefCountedMemory> raw_data(
1266             ReadFileData(s2f->second));
1267         if (!raw_data.get() || !raw_data->size()) {
1268           LOG(ERROR) << "Could not load theme image"
1269                      << " prs_id=" << prs_id
1270                      << " scale_factor_enum=" << scale_factor
1271                      << " file=" << s2f->second.value()
1272                      << (raw_data.get() ? " (zero size)" : " (read error)");
1273           return false;
1274         }
1275         if (is_copyable) {
1276           int raw_id = GetRawIDByPersistentID(prs_id, scale_factor);
1277           image_memory_[raw_id] = raw_data;
1278         } else {
1279           SkBitmap bitmap;
1280           if (gfx::PNGCodec::Decode(raw_data->front(), raw_data->size(),
1281                                     &bitmap)) {
1282             image_skia.AddRepresentation(
1283                 gfx::ImageSkiaRep(bitmap,
1284                                   ui::GetImageScale(scale_factor)));
1285           } else {
1286             NOTREACHED() << "Unable to decode theme image resource "
1287                          << it->first;
1288           }
1289         }
1290       }
1291     }
1292     if (!is_copyable && !image_skia.isNull())
1293       (*image_cache)[prs_id] = gfx::Image(image_skia);
1294   }
1295
1296   return true;
1297 }
1298
1299 void BrowserThemePack::CreateImages(ImageCache* images) const {
1300   CropImages(images);
1301   CreateFrameImages(images);
1302   CreateTintedButtons(GetTintInternal(ThemeProperties::TINT_BUTTONS), images);
1303   CreateTabBackgroundImages(images);
1304 }
1305
1306 void BrowserThemePack::CropImages(ImageCache* images) const {
1307   bool has_frame_border = HasFrameBorder();
1308   for (size_t i = 0; i < arraysize(kImagesToCrop); ++i) {
1309     if (has_frame_border && kImagesToCrop[i].skip_if_frame_border)
1310       continue;
1311
1312     int prs_id = kImagesToCrop[i].prs_id;
1313     ImageCache::iterator it = images->find(prs_id);
1314     if (it == images->end())
1315       continue;
1316
1317     int crop_height = kImagesToCrop[i].max_height;
1318     gfx::ImageSkia image_skia = it->second.AsImageSkia();
1319     (*images)[prs_id] = gfx::Image(gfx::ImageSkiaOperations::ExtractSubset(
1320         image_skia, gfx::Rect(0, 0, image_skia.width(), crop_height)));
1321   }
1322 }
1323
1324 void BrowserThemePack::CreateFrameImages(ImageCache* images) const {
1325   ResourceBundle& rb = ResourceBundle::GetSharedInstance();
1326
1327   // Create all the output images in a separate cache and move them back into
1328   // the input images because there can be name collisions.
1329   ImageCache temp_output;
1330
1331   for (size_t i = 0; i < arraysize(kFrameTintMap); ++i) {
1332     int prs_id = kFrameTintMap[i].key;
1333     gfx::Image frame;
1334     // If there's no frame image provided for the specified id, then load
1335     // the default provided frame. If that's not provided, skip this whole
1336     // thing and just use the default images.
1337     int prs_base_id = 0;
1338
1339 #if defined(OS_WIN)
1340     if (prs_id == PRS_THEME_FRAME_INCOGNITO_INACTIVE_WIN) {
1341       prs_base_id = images->count(PRS_THEME_FRAME_INCOGNITO_WIN) ?
1342                     PRS_THEME_FRAME_INCOGNITO_WIN : PRS_THEME_FRAME_WIN;
1343     } else if (prs_id == PRS_THEME_FRAME_INACTIVE_WIN) {
1344       prs_base_id = PRS_THEME_FRAME_WIN;
1345     } else if (prs_id == PRS_THEME_FRAME_INCOGNITO_WIN &&
1346                 !images->count(PRS_THEME_FRAME_INCOGNITO_WIN)) {
1347       prs_base_id = PRS_THEME_FRAME_WIN;
1348     }
1349 #endif
1350     if (!prs_base_id) {
1351       if (prs_id == PRS_THEME_FRAME_INCOGNITO_INACTIVE) {
1352         prs_base_id = images->count(PRS_THEME_FRAME_INCOGNITO) ?
1353                       PRS_THEME_FRAME_INCOGNITO : PRS_THEME_FRAME;
1354       } else if (prs_id == PRS_THEME_FRAME_OVERLAY_INACTIVE) {
1355         prs_base_id = PRS_THEME_FRAME_OVERLAY;
1356       } else if (prs_id == PRS_THEME_FRAME_INACTIVE) {
1357         prs_base_id = PRS_THEME_FRAME;
1358       } else if (prs_id == PRS_THEME_FRAME_INCOGNITO &&
1359                  !images->count(PRS_THEME_FRAME_INCOGNITO)) {
1360         prs_base_id = PRS_THEME_FRAME;
1361       } else {
1362         prs_base_id = prs_id;
1363       }
1364     }
1365     if (images->count(prs_id)) {
1366       frame = (*images)[prs_id];
1367     } else if (prs_base_id != prs_id && images->count(prs_base_id)) {
1368       frame = (*images)[prs_base_id];
1369     } else if (prs_base_id == PRS_THEME_FRAME_OVERLAY) {
1370 #if defined(OS_WIN)
1371       if (images->count(PRS_THEME_FRAME_WIN)) {
1372 #else
1373       if (images->count(PRS_THEME_FRAME)) {
1374 #endif
1375         // If there is no theme overlay, don't tint the default frame,
1376         // because it will overwrite the custom frame image when we cache and
1377         // reload from disk.
1378         frame = gfx::Image();
1379       }
1380     } else {
1381       // If the theme doesn't specify an image, then apply the tint to
1382       // the default frame.
1383       frame = rb.GetImageNamed(IDR_THEME_FRAME);
1384 #if defined(OS_WIN) && defined(USE_AURA)
1385       if (prs_id >= PRS_THEME_FRAME_WIN &&
1386           prs_id <= PRS_THEME_FRAME_INCOGNITO_INACTIVE_WIN) {
1387         frame = rb.GetImageNamed(IDR_THEME_FRAME_WIN);
1388       }
1389 #endif
1390     }
1391     if (!frame.IsEmpty()) {
1392       temp_output[prs_id] = CreateHSLShiftedImage(
1393           frame, GetTintInternal(kFrameTintMap[i].value));
1394     }
1395   }
1396   MergeImageCaches(temp_output, images);
1397 }
1398
1399 void BrowserThemePack::CreateTintedButtons(
1400     const color_utils::HSL& button_tint,
1401     ImageCache* processed_images) const {
1402   if (button_tint.h != -1 || button_tint.s != -1 || button_tint.l != -1) {
1403     ResourceBundle& rb = ResourceBundle::GetSharedInstance();
1404     const std::set<int>& idr_ids =
1405         ThemeProperties::GetTintableToolbarButtons();
1406     for (std::set<int>::const_iterator it = idr_ids.begin();
1407          it != idr_ids.end(); ++it) {
1408       int prs_id = GetPersistentIDByIDR(*it);
1409       DCHECK(prs_id > 0);
1410
1411       // Fetch the image by IDR...
1412       gfx::Image& button = rb.GetImageNamed(*it);
1413
1414       // but save a version with the persistent ID.
1415       (*processed_images)[prs_id] =
1416           CreateHSLShiftedImage(button, button_tint);
1417     }
1418   }
1419 }
1420
1421 void BrowserThemePack::CreateTabBackgroundImages(ImageCache* images) const {
1422   ImageCache temp_output;
1423   for (size_t i = 0; i < arraysize(kTabBackgroundMap); ++i) {
1424     int prs_id = kTabBackgroundMap[i].key;
1425     int prs_base_id = kTabBackgroundMap[i].value;
1426
1427     // We only need to generate the background tab images if we were provided
1428     // with a PRS_THEME_FRAME.
1429     ImageCache::const_iterator it = images->find(prs_base_id);
1430     if (it != images->end()) {
1431       gfx::ImageSkia image_to_tint = (it->second).AsImageSkia();
1432       color_utils::HSL hsl_shift = GetTintInternal(
1433           ThemeProperties::TINT_BACKGROUND_TAB);
1434       int vertical_offset = images->count(prs_id)
1435                             ? kRestoredTabVerticalOffset : 0;
1436
1437       gfx::ImageSkia overlay;
1438       ImageCache::const_iterator overlay_it = images->find(prs_id);
1439       if (overlay_it != images->end())
1440         overlay = overlay_it->second.AsImageSkia();
1441
1442       gfx::ImageSkiaSource* source = new TabBackgroundImageSource(
1443           image_to_tint, overlay, hsl_shift, vertical_offset);
1444       // ImageSkia takes ownership of |source|.
1445       temp_output[prs_id] = gfx::Image(gfx::ImageSkia(source,
1446           image_to_tint.size()));
1447     }
1448   }
1449   MergeImageCaches(temp_output, images);
1450 }
1451
1452 void BrowserThemePack::RepackImages(const ImageCache& images,
1453                                     RawImages* reencoded_images) const {
1454   typedef std::vector<ui::ScaleFactor> ScaleFactors;
1455   for (ImageCache::const_iterator it = images.begin();
1456        it != images.end(); ++it) {
1457     gfx::ImageSkia image_skia = *it->second.ToImageSkia();
1458
1459     typedef std::vector<gfx::ImageSkiaRep> ImageSkiaReps;
1460     ImageSkiaReps image_reps = image_skia.image_reps();
1461     if (image_reps.empty()) {
1462       NOTREACHED() << "No image reps for resource " << it->first << ".";
1463     }
1464     for (ImageSkiaReps::iterator rep_it = image_reps.begin();
1465          rep_it != image_reps.end(); ++rep_it) {
1466       std::vector<unsigned char> bitmap_data;
1467       if (!gfx::PNGCodec::EncodeBGRASkBitmap(rep_it->sk_bitmap(), false,
1468                                              &bitmap_data)) {
1469         NOTREACHED() << "Image file for resource " << it->first
1470                      << " could not be encoded.";
1471       }
1472       int raw_id = GetRawIDByPersistentID(
1473           it->first,
1474           ui::GetSupportedScaleFactor(rep_it->scale()));
1475       (*reencoded_images)[raw_id] =
1476           base::RefCountedBytes::TakeVector(&bitmap_data);
1477     }
1478   }
1479 }
1480
1481 void BrowserThemePack::MergeImageCaches(
1482     const ImageCache& source, ImageCache* destination) const {
1483   for (ImageCache::const_iterator it = source.begin(); it != source.end();
1484        ++it) {
1485     (*destination)[it->first] = it->second;
1486   }
1487 }
1488
1489 void BrowserThemePack::AddRawImagesTo(const RawImages& images,
1490                                       RawDataForWriting* out) const {
1491   for (RawImages::const_iterator it = images.begin(); it != images.end();
1492        ++it) {
1493     (*out)[it->first] = base::StringPiece(
1494         it->second->front_as<char>(), it->second->size());
1495   }
1496 }
1497
1498 color_utils::HSL BrowserThemePack::GetTintInternal(int id) const {
1499   if (tints_) {
1500     for (size_t i = 0; i < kTintTableLength; ++i) {
1501       if (tints_[i].id == id) {
1502         color_utils::HSL hsl;
1503         hsl.h = tints_[i].h;
1504         hsl.s = tints_[i].s;
1505         hsl.l = tints_[i].l;
1506         return hsl;
1507       }
1508     }
1509   }
1510
1511   return ThemeProperties::GetDefaultTint(id);
1512 }
1513
1514 int BrowserThemePack::GetRawIDByPersistentID(
1515     int prs_id,
1516     ui::ScaleFactor scale_factor) const {
1517   if (prs_id < 0)
1518     return -1;
1519
1520   for (size_t i = 0; i < scale_factors_.size(); ++i) {
1521     if (scale_factors_[i] == scale_factor)
1522       return static_cast<int>(kPersistingImagesLength * i) + prs_id;
1523   }
1524   return -1;
1525 }
1526
1527 bool BrowserThemePack::GetScaleFactorFromManifestKey(
1528     const std::string& key,
1529     ui::ScaleFactor* scale_factor) const {
1530   int percent = 0;
1531   if (base::StringToInt(key, &percent)) {
1532     float scale = static_cast<float>(percent) / 100.0f;
1533     for (size_t i = 0; i < scale_factors_.size(); ++i) {
1534       if (fabs(ui::GetImageScale(scale_factors_[i]) - scale) < 0.001) {
1535         *scale_factor = scale_factors_[i];
1536         return true;
1537       }
1538     }
1539   }
1540   return false;
1541 }
1542
1543 void BrowserThemePack::GenerateRawImageForAllSupportedScales(int prs_id) {
1544   // Compute (by scaling) bitmaps for |prs_id| for any scale factors
1545   // for which the theme author did not provide a bitmap. We compute
1546   // the bitmaps using the highest scale factor that theme author
1547   // provided.
1548   // Note: We use only supported scale factors. For example, if scale
1549   // factor 2x is supported by the current system, but 1.8x is not and
1550   // if the theme author did not provide an image for 2x but one for
1551   // 1.8x, we will not use the 1.8x image here. Here we will only use
1552   // images provided for scale factors supported by the current system.
1553
1554   // See if any image is missing. If not, we're done.
1555   bool image_missing = false;
1556   for (size_t i = 0; i < scale_factors_.size(); ++i) {
1557     int raw_id = GetRawIDByPersistentID(prs_id, scale_factors_[i]);
1558     if (image_memory_.find(raw_id) == image_memory_.end()) {
1559       image_missing = true;
1560       break;
1561     }
1562   }
1563   if (!image_missing)
1564     return;
1565
1566   // Find available scale factor with highest scale.
1567   ui::ScaleFactor available_scale_factor = ui::SCALE_FACTOR_NONE;
1568   for (size_t i = 0; i < scale_factors_.size(); ++i) {
1569     int raw_id = GetRawIDByPersistentID(prs_id, scale_factors_[i]);
1570     if ((available_scale_factor == ui::SCALE_FACTOR_NONE ||
1571          (ui::GetImageScale(scale_factors_[i]) >
1572           ui::GetImageScale(available_scale_factor))) &&
1573         image_memory_.find(raw_id) != image_memory_.end()) {
1574       available_scale_factor = scale_factors_[i];
1575     }
1576   }
1577   // If no scale factor is available, we're done.
1578   if (available_scale_factor == ui::SCALE_FACTOR_NONE)
1579     return;
1580
1581   // Get bitmap for the available scale factor.
1582   int available_raw_id = GetRawIDByPersistentID(prs_id, available_scale_factor);
1583   RawImages::const_iterator it = image_memory_.find(available_raw_id);
1584   SkBitmap available_bitmap;
1585   if (!gfx::PNGCodec::Decode(it->second->front(),
1586                              it->second->size(),
1587                              &available_bitmap)) {
1588     NOTREACHED() << "Unable to decode theme image for prs_id="
1589                  << prs_id << " for scale_factor=" << available_scale_factor;
1590     return;
1591   }
1592
1593   // Fill in all missing scale factors by scaling the available bitmap.
1594   for (size_t i = 0; i < scale_factors_.size(); ++i) {
1595     int scaled_raw_id = GetRawIDByPersistentID(prs_id, scale_factors_[i]);
1596     if (image_memory_.find(scaled_raw_id) != image_memory_.end())
1597       continue;
1598     SkBitmap scaled_bitmap =
1599         CreateLowQualityResizedBitmap(available_bitmap,
1600                                       available_scale_factor,
1601                                       scale_factors_[i]);
1602     std::vector<unsigned char> bitmap_data;
1603     if (!gfx::PNGCodec::EncodeBGRASkBitmap(scaled_bitmap,
1604                                            false,
1605                                            &bitmap_data)) {
1606       NOTREACHED() << "Unable to encode theme image for prs_id="
1607                    << prs_id << " for scale_factor=" << scale_factors_[i];
1608       break;
1609     }
1610     image_memory_[scaled_raw_id] =
1611         base::RefCountedBytes::TakeVector(&bitmap_data);
1612   }
1613 }