chrome/browser/ui/browser_navigator.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/ui/browser_navigator.h"
   6
   7 #include <algorithm>
   8
   9 #include "base/command_line.h"
  10 #include "base/prefs/pref_service.h"
  11 #include "base/strings/stringprintf.h"
  12 #include "base/strings/utf_string_conversions.h"
  13 #include "chrome/browser/browser_about_handler.h"
  14 #include "chrome/browser/chrome_notification_types.h"
  15 #include "chrome/browser/prefs/incognito_mode_prefs.h"
  16 #include "chrome/browser/prerender/prerender_manager.h"
  17 #include "chrome/browser/prerender/prerender_manager_factory.h"
  18 #include "chrome/browser/profiles/profile.h"
  19 #include "chrome/browser/tab_contents/tab_util.h"
  20 #include "chrome/browser/ui/browser.h"
  21 #include "chrome/browser/ui/browser_finder.h"
  22 #include "chrome/browser/ui/browser_instant_controller.h"
  23 #include "chrome/browser/ui/browser_window.h"
  24 #include "chrome/browser/ui/host_desktop.h"
  25 #include "chrome/browser/ui/location_bar/location_bar.h"
  26 #include "chrome/browser/ui/search/instant_search_prerenderer.h"
  27 #include "chrome/browser/ui/singleton_tabs.h"
  28 #include "chrome/browser/ui/status_bubble.h"
  29 #include "chrome/browser/ui/tab_helpers.h"
  30 #include "chrome/browser/ui/tabs/tab_strip_model.h"
  31 #include "chrome/common/url_constants.h"
  32 #include "content/public/browser/browser_url_handler.h"
  33 #include "content/public/browser/navigation_entry.h"
  34 #include "content/public/browser/notification_service.h"
  35 #include "content/public/browser/render_view_host.h"
  36 #include "content/public/browser/web_contents.h"
  37
  38 #if defined(USE_ASH)
  39 #include "chrome/browser/ui/ash/multi_user/multi_user_window_manager.h"
  40 #endif
  41
  42 #if defined(USE_AURA)
  43 #include "ui/aura/window.h"
  44 #endif
  45
  46 #if defined(ENABLE_EXTENSIONS)
  47 #include "chrome/browser/extensions/tab_helper.h"
  48 #include "chrome/browser/web_applications/web_app.h"
  49 #include "extensions/browser/extension_registry.h"
  50 #include "extensions/common/extension.h"
  51 #include "extensions/common/extension_set.h"
  52 #endif
  53
  54 using content::GlobalRequestID;
  55 using content::NavigationController;
  56 using content::WebContents;
  57
  58 class BrowserNavigatorWebContentsAdoption {
  59  public:
  60   static void AttachTabHelpers(content::WebContents* contents) {
  61     TabHelpers::AttachTabHelpers(contents);
  62   }
  63 };
  64
  65 namespace {
  66
  67 // Returns true if the specified Browser can open tabs. Not all Browsers support
  68 // multiple tabs, such as app frames and popups. This function returns false for
  69 // those types of Browser.
  70 bool WindowCanOpenTabs(Browser* browser) {
  71   return browser->CanSupportWindowFeature(Browser::FEATURE_TABSTRIP) ||
  72       browser->tab_strip_model()->empty();
  73 }
  74
  75 // Finds an existing Browser compatible with |profile|, making a new one if no
  76 // such Browser is located.
  77 Browser* GetOrCreateBrowser(Profile* profile,
  78                             chrome::HostDesktopType host_desktop_type) {
  79   Browser* browser = chrome::FindTabbedBrowser(profile, false,
  80                                                host_desktop_type);
  81   return browser ? browser : new Browser(
  82       Browser::CreateParams(profile, host_desktop_type));
  83 }
  84
  85 // Change some of the navigation parameters based on the particular URL.
  86 // Currently this applies to some chrome:// pages which we always want to open
  87 // in a non-incognito window. Note that even though a ChromeOS guest session is
  88 // technically an incognito window, these URLs are allowed.
  89 // Returns true on success. Otherwise, if changing params leads the browser into
  90 // an erroneous state, returns false.
  91 bool AdjustNavigateParamsForURL(chrome::NavigateParams* params) {
  92   if (params->target_contents != NULL ||
  93       chrome::IsURLAllowedInIncognito(params->url,
  94                                       params->initiating_profile) ||
  95       params->initiating_profile->IsGuestSession()) {
  96     return true;
  97   }
  98
  99   Profile* profile = params->initiating_profile;
 100
 101   if (profile->IsOffTheRecord() || params->disposition == OFF_THE_RECORD) {
 102     profile = profile->GetOriginalProfile();
 103
 104     // If incognito is forced, we punt.
 105     PrefService* prefs = profile->GetPrefs();
 106     if (prefs && IncognitoModePrefs::GetAvailability(prefs) ==
 107             IncognitoModePrefs::FORCED) {
 108       return false;
 109     }
 110
 111     params->disposition = SINGLETON_TAB;
 112     params->browser = GetOrCreateBrowser(profile, params->host_desktop_type);
 113     params->window_action = chrome::NavigateParams::SHOW_WINDOW;
 114   }
 115
 116   return true;
 117 }
 118
 119 // Returns a Browser that can host the navigation or tab addition specified in
 120 // |params|. This might just return the same Browser specified in |params|, or
 121 // some other if that Browser is deemed incompatible.
 122 Browser* GetBrowserForDisposition(chrome::NavigateParams* params) {
 123   // If no source WebContents was specified, we use the selected one from
 124   // the target browser. This must happen first, before
 125   // GetBrowserForDisposition() has a chance to replace |params->browser| with
 126   // another one.
 127   if (!params->source_contents && params->browser) {
 128     params->source_contents =
 129         params->browser->tab_strip_model()->GetActiveWebContents();
 130   }
 131
 132   Profile* profile = params->initiating_profile;
 133
 134   switch (params->disposition) {
 135     case CURRENT_TAB:
 136       if (params->browser)
 137         return params->browser;
 138       // Find a compatible window and re-execute this command in it. Otherwise
 139       // re-run with NEW_WINDOW.
 140       return GetOrCreateBrowser(profile, params->host_desktop_type);
 141     case SINGLETON_TAB:
 142     case NEW_FOREGROUND_TAB:
 143     case NEW_BACKGROUND_TAB:
 144       // See if we can open the tab in the window this navigator is bound to.
 145       if (params->browser && WindowCanOpenTabs(params->browser))
 146         return params->browser;
 147       // Find a compatible window and re-execute this command in it. Otherwise
 148       // re-run with NEW_WINDOW.
 149       return GetOrCreateBrowser(profile, params->host_desktop_type);
 150     case NEW_POPUP: {
 151       // Make a new popup window.
 152       // Coerce app-style if |source| represents an app.
 153       std::string app_name;
 154 #if defined(ENABLE_EXTENSIONS)
 155       if (!params->extension_app_id.empty()) {
 156         app_name = web_app::GenerateApplicationNameFromExtensionId(
 157             params->extension_app_id);
 158       } else if (params->browser && !params->browser->app_name().empty()) {
 159         app_name = params->browser->app_name();
 160       } else if (params->source_contents) {
 161         extensions::TabHelper* extensions_tab_helper =
 162             extensions::TabHelper::FromWebContents(params->source_contents);
 163         if (extensions_tab_helper && extensions_tab_helper->is_app()) {
 164           app_name = web_app::GenerateApplicationNameFromExtensionId(
 165               extensions_tab_helper->extension_app()->id());
 166         }
 167       }
 168 #endif
 169       if (app_name.empty()) {
 170         Browser::CreateParams browser_params(
 171             Browser::TYPE_POPUP, profile, params->host_desktop_type);
 172         browser_params.trusted_source = params->trusted_source;
 173         browser_params.initial_bounds = params->window_bounds;
 174         return new Browser(browser_params);
 175       }
 176
 177       return new Browser(Browser::CreateParams::CreateForApp(
 178           app_name,
 179           params->trusted_source,
 180           params->window_bounds,
 181           profile,
 182           params->host_desktop_type));
 183     }
 184     case NEW_WINDOW: {
 185       // Make a new normal browser window.
 186       return new Browser(Browser::CreateParams(profile,
 187                                                params->host_desktop_type));
 188     }
 189     case OFF_THE_RECORD:
 190       // Make or find an incognito window.
 191       return GetOrCreateBrowser(profile->GetOffTheRecordProfile(),
 192                                 params->host_desktop_type);
 193     // The following types all result in no navigation.
 194     case SUPPRESS_OPEN:
 195     case SAVE_TO_DISK:
 196     case IGNORE_ACTION:
 197       return NULL;
 198     default:
 199       NOTREACHED();
 200   }
 201   return NULL;
 202 }
 203
 204 // Fix disposition and other parameter values depending on prevailing
 205 // conditions.
 206 void NormalizeDisposition(chrome::NavigateParams* params) {
 207   // Calculate the WindowOpenDisposition if necessary.
 208   if (params->browser->tab_strip_model()->empty() &&
 209       (params->disposition == NEW_BACKGROUND_TAB ||
 210        params->disposition == CURRENT_TAB ||
 211        params->disposition == SINGLETON_TAB)) {
 212     params->disposition = NEW_FOREGROUND_TAB;
 213   }
 214   if (params->browser->profile()->IsOffTheRecord() &&
 215       params->disposition == OFF_THE_RECORD) {
 216     params->disposition = NEW_FOREGROUND_TAB;
 217   }
 218   if (!params->source_contents && params->disposition == CURRENT_TAB)
 219     params->disposition = NEW_FOREGROUND_TAB;
 220
 221   switch (params->disposition) {
 222     case NEW_BACKGROUND_TAB:
 223       // Disposition trumps add types. ADD_ACTIVE is a default, so we need to
 224       // remove it if disposition implies the tab is going to open in the
 225       // background.
 226       params->tabstrip_add_types &= ~TabStripModel::ADD_ACTIVE;
 227       break;
 228
 229     case NEW_WINDOW:
 230     case NEW_POPUP:
 231       // Code that wants to open a new window typically expects it to be shown
 232       // automatically.
 233       if (params->window_action == chrome::NavigateParams::NO_ACTION)
 234         params->window_action = chrome::NavigateParams::SHOW_WINDOW;
 235       // Fall-through.
 236     case NEW_FOREGROUND_TAB:
 237     case SINGLETON_TAB:
 238       params->tabstrip_add_types |= TabStripModel::ADD_ACTIVE;
 239       break;
 240
 241     default:
 242       break;
 243   }
 244 }
 245
 246 // Obtain the profile used by the code that originated the Navigate() request.
 247 Profile* GetSourceProfile(chrome::NavigateParams* params) {
 248   if (params->source_contents) {
 249     return Profile::FromBrowserContext(
 250         params->source_contents->GetBrowserContext());
 251   }
 252
 253   return params->initiating_profile;
 254 }
 255
 256 void LoadURLInContents(WebContents* target_contents,
 257                        const GURL& url,
 258                        chrome::NavigateParams* params) {
 259   NavigationController::LoadURLParams load_url_params(url);
 260   load_url_params.source_site_instance = params->source_site_instance;
 261   load_url_params.referrer = params->referrer;
 262   load_url_params.frame_tree_node_id = params->frame_tree_node_id;
 263   load_url_params.redirect_chain = params->redirect_chain;
 264   load_url_params.transition_type = params->transition;
 265   load_url_params.extra_headers = params->extra_headers;
 266   load_url_params.should_replace_current_entry =
 267       params->should_replace_current_entry;
 268
 269   if (params->transferred_global_request_id != GlobalRequestID()) {
 270     load_url_params.is_renderer_initiated = params->is_renderer_initiated;
 271     load_url_params.transferred_global_request_id =
 272         params->transferred_global_request_id;
 273   } else if (params->is_renderer_initiated) {
 274     load_url_params.is_renderer_initiated = true;
 275   }
 276
 277   // Only allows the browser-initiated navigation to use POST.
 278   if (params->uses_post && !params->is_renderer_initiated) {
 279     load_url_params.load_type =
 280         NavigationController::LOAD_TYPE_BROWSER_INITIATED_HTTP_POST;
 281     load_url_params.browser_initiated_post_data =
 282         params->browser_initiated_post_data;
 283   }
 284   target_contents->GetController().LoadURLWithParams(load_url_params);
 285 }
 286
 287 // This class makes sure the Browser object held in |params| is made visible
 288 // by the time it goes out of scope, provided |params| wants it to be shown.
 289 class ScopedBrowserShower {
 290  public:
 291   explicit ScopedBrowserShower(chrome::NavigateParams* params)
 292       : params_(params) {
 293   }
 294   ~ScopedBrowserShower() {
 295     if (params_->window_action ==
 296         chrome::NavigateParams::SHOW_WINDOW_INACTIVE) {
 297       params_->browser->window()->ShowInactive();
 298     } else if (params_->window_action == chrome::NavigateParams::SHOW_WINDOW) {
 299       params_->browser->window()->Show();
 300       // If a user gesture opened a popup window, focus the contents.
 301       if (params_->user_gesture && params_->disposition == NEW_POPUP &&
 302           params_->target_contents) {
 303         params_->target_contents->Focus();
 304       }
 305     }
 306   }
 307
 308  private:
 309   chrome::NavigateParams* params_;
 310   DISALLOW_COPY_AND_ASSIGN(ScopedBrowserShower);
 311 };
 312
 313 // This class manages the lifetime of a WebContents created by the
 314 // Navigate() function. When Navigate() creates a WebContents for a URL,
 315 // an instance of this class takes ownership of it via TakeOwnership() until the
 316 // WebContents is added to a tab strip at which time ownership is
 317 // relinquished via ReleaseOwnership(). If this object goes out of scope without
 318 // being added to a tab strip, the created WebContents is deleted to
 319 // avoid a leak and the params->target_contents field is set to NULL.
 320 class ScopedTargetContentsOwner {
 321  public:
 322   explicit ScopedTargetContentsOwner(chrome::NavigateParams* params)
 323       : params_(params) {
 324   }
 325   ~ScopedTargetContentsOwner() {
 326     if (target_contents_owner_.get())
 327       params_->target_contents = NULL;
 328   }
 329
 330   // Assumes ownership of |params_|' target_contents until ReleaseOwnership
 331   // is called.
 332   void TakeOwnership() {
 333     target_contents_owner_.reset(params_->target_contents);
 334   }
 335
 336   // Relinquishes ownership of |params_|' target_contents.
 337   WebContents* ReleaseOwnership() {
 338     return target_contents_owner_.release();
 339   }
 340
 341  private:
 342   chrome::NavigateParams* params_;
 343   scoped_ptr<WebContents> target_contents_owner_;
 344   DISALLOW_COPY_AND_ASSIGN(ScopedTargetContentsOwner);
 345 };
 346
 347 content::WebContents* CreateTargetContents(const chrome::NavigateParams& params,
 348                                            const GURL& url) {
 349   WebContents::CreateParams create_params(
 350       params.browser->profile(),
 351       tab_util::GetSiteInstanceForNewTab(params.browser->profile(), url));
 352   if (params.source_contents) {
 353     create_params.initial_size =
 354         params.source_contents->GetContainerBounds().size();
 355     create_params.created_with_opener = params.created_with_opener;
 356   }
 357   if (params.disposition == NEW_BACKGROUND_TAB)
 358     create_params.initially_hidden = true;
 359
 360 #if defined(USE_AURA)
 361   if (params.browser->window() &&
 362       params.browser->window()->GetNativeWindow()) {
 363     create_params.context =
 364         params.browser->window()->GetNativeWindow();
 365   }
 366 #endif
 367
 368   WebContents* target_contents = WebContents::Create(create_params);
 369
 370   // New tabs can have WebUI URLs that will make calls back to arbitrary
 371   // tab helpers, so the entire set of tab helpers needs to be set up
 372   // immediately.
 373   BrowserNavigatorWebContentsAdoption::AttachTabHelpers(target_contents);
 374 #if defined(ENABLE_EXTENSIONS)
 375   extensions::TabHelper::FromWebContents(target_contents)->
 376       SetExtensionAppById(params.extension_app_id);
 377 #endif
 378   return target_contents;
 379 }
 380
 381 // If a prerendered page exists for |url|, replace the page at
 382 // |params->target_contents| with it and update to point to the swapped-in
 383 // WebContents.
 384 bool SwapInPrerender(const GURL& url, chrome::NavigateParams* params) {
 385   Profile* profile =
 386       Profile::FromBrowserContext(params->target_contents->GetBrowserContext());
 387   InstantSearchPrerenderer* prerenderer =
 388       InstantSearchPrerenderer::GetForProfile(profile);
 389   if (prerenderer && prerenderer->UsePrerenderedPage(url, params))
 390     return true;
 391
 392   prerender::PrerenderManager* prerender_manager =
 393       prerender::PrerenderManagerFactory::GetForProfile(profile);
 394   return prerender_manager &&
 395       prerender_manager->MaybeUsePrerenderedPage(url, params);
 396 }
 397
 398 chrome::HostDesktopType GetHostDesktop(Browser* browser) {
 399   if (browser)
 400     return browser->host_desktop_type();
 401   return chrome::GetActiveDesktop();
 402 }
 403
 404 }  // namespace
 405
 406 namespace chrome {
 407
 408 NavigateParams::NavigateParams(Browser* a_browser,
 409                                const GURL& a_url,
 410                                ui::PageTransition a_transition)
 411     : url(a_url),
 412       frame_tree_node_id(-1),
 413       uses_post(false),
 414       target_contents(NULL),
 415       source_contents(NULL),
 416       disposition(CURRENT_TAB),
 417       trusted_source(false),
 418       transition(a_transition),
 419       is_renderer_initiated(false),
 420       tabstrip_index(-1),
 421       tabstrip_add_types(TabStripModel::ADD_ACTIVE),
 422       window_action(NO_ACTION),
 423       user_gesture(true),
 424       path_behavior(RESPECT),
 425       ref_behavior(IGNORE_REF),
 426       browser(a_browser),
 427       initiating_profile(NULL),
 428       host_desktop_type(GetHostDesktop(a_browser)),
 429       should_replace_current_entry(false),
 430       created_with_opener(false) {
 431 }
 432
 433 NavigateParams::NavigateParams(Browser* a_browser,
 434                                WebContents* a_target_contents)
 435     : frame_tree_node_id(-1),
 436       uses_post(false),
 437       target_contents(a_target_contents),
 438       source_contents(NULL),
 439       disposition(CURRENT_TAB),
 440       trusted_source(false),
 441       transition(ui::PAGE_TRANSITION_LINK),
 442       is_renderer_initiated(false),
 443       tabstrip_index(-1),
 444       tabstrip_add_types(TabStripModel::ADD_ACTIVE),
 445       window_action(NO_ACTION),
 446       user_gesture(true),
 447       path_behavior(RESPECT),
 448       ref_behavior(IGNORE_REF),
 449       browser(a_browser),
 450       initiating_profile(NULL),
 451       host_desktop_type(GetHostDesktop(a_browser)),
 452       should_replace_current_entry(false),
 453       created_with_opener(false) {
 454 }
 455
 456 NavigateParams::NavigateParams(Profile* a_profile,
 457                                const GURL& a_url,
 458                                ui::PageTransition a_transition)
 459     : url(a_url),
 460       frame_tree_node_id(-1),
 461       uses_post(false),
 462       target_contents(NULL),
 463       source_contents(NULL),
 464       disposition(NEW_FOREGROUND_TAB),
 465       trusted_source(false),
 466       transition(a_transition),
 467       is_renderer_initiated(false),
 468       tabstrip_index(-1),
 469       tabstrip_add_types(TabStripModel::ADD_ACTIVE),
 470       window_action(SHOW_WINDOW),
 471       user_gesture(true),
 472       path_behavior(RESPECT),
 473       ref_behavior(IGNORE_REF),
 474       browser(NULL),
 475       initiating_profile(a_profile),
 476       host_desktop_type(chrome::GetActiveDesktop()),
 477       should_replace_current_entry(false),
 478       created_with_opener(false) {
 479 }
 480
 481 NavigateParams::~NavigateParams() {}
 482
 483 void FillNavigateParamsFromOpenURLParams(chrome::NavigateParams* nav_params,
 484                                          const content::OpenURLParams& params) {
 485   nav_params->referrer = params.referrer;
 486   nav_params->source_site_instance = params.source_site_instance;
 487   nav_params->frame_tree_node_id = params.frame_tree_node_id;
 488   nav_params->redirect_chain = params.redirect_chain;
 489   nav_params->extra_headers = params.extra_headers;
 490   nav_params->disposition = params.disposition;
 491   nav_params->trusted_source = false;
 492   nav_params->is_renderer_initiated = params.is_renderer_initiated;
 493   nav_params->transferred_global_request_id =
 494       params.transferred_global_request_id;
 495   nav_params->should_replace_current_entry =
 496       params.should_replace_current_entry;
 497   nav_params->uses_post = params.uses_post;
 498   nav_params->browser_initiated_post_data = params.browser_initiated_post_data;
 499 }
 500
 501 void Navigate(NavigateParams* params) {
 502   Browser* source_browser = params->browser;
 503   if (source_browser)
 504     params->initiating_profile = source_browser->profile();
 505   DCHECK(params->initiating_profile);
 506
 507   if (!AdjustNavigateParamsForURL(params))
 508     return;
 509
 510 #if defined(ENABLE_EXTENSIONS)
 511   const extensions::Extension* extension =
 512     extensions::ExtensionRegistry::Get(params->initiating_profile)->
 513         enabled_extensions().GetExtensionOrAppByURL(params->url);
 514   // Platform apps cannot navigate. Block the request.
 515   if (extension && extension->is_platform_app())
 516     params->url = GURL(chrome::kExtensionInvalidRequestURL);
 517 #endif
 518
 519   // The browser window may want to adjust the disposition.
 520   if (params->disposition == NEW_POPUP &&
 521       source_browser &&
 522       source_browser->window()) {
 523     params->disposition =
 524         source_browser->window()->GetDispositionForPopupBounds(
 525             params->window_bounds);
 526   }
 527
 528   params->browser = GetBrowserForDisposition(params);
 529   if (!params->browser)
 530     return;
 531
 532 #if defined(USE_ASH)
 533   if (source_browser && source_browser != params->browser) {
 534     // When the newly created browser was spawned by a browser which visits
 535     // another user's desktop, it should be shown on the same desktop as the
 536     // originating one. (This is part of the desktop separation per profile).
 537     MultiUserWindowManager* manager = MultiUserWindowManager::GetInstance();
 538     // Some unit tests have no manager instantiated.
 539     if (manager) {
 540       aura::Window* src_window = source_browser->window()->GetNativeWindow();
 541       aura::Window* new_window = params->browser->window()->GetNativeWindow();
 542       const std::string& src_user =
 543           manager->GetUserPresentingWindow(src_window);
 544       if (src_user != manager->GetUserPresentingWindow(new_window)) {
 545         // Once the window gets presented, it should be shown on the same
 546         // desktop as the desktop of the creating browser. Note that this
 547         // command will not show the window if it wasn't shown yet by the
 548         // browser creation.
 549         manager->ShowWindowForUser(new_window, src_user);
 550       }
 551     }
 552   }
 553 #endif
 554
 555   // Navigate() must not return early after this point.
 556
 557   if (GetSourceProfile(params) != params->browser->profile()) {
 558     // A tab is being opened from a link from a different profile, we must reset
 559     // source information that may cause state to be shared.
 560     params->source_contents = NULL;
 561     params->referrer = content::Referrer();
 562   }
 563
 564   // Make sure the Browser is shown if params call for it.
 565   ScopedBrowserShower shower(params);
 566
 567   // Makes sure any WebContents created by this function is destroyed if
 568   // not properly added to a tab strip.
 569   ScopedTargetContentsOwner target_contents_owner(params);
 570
 571   // Some dispositions need coercion to base types.
 572   NormalizeDisposition(params);
 573
 574   // If a new window has been created, it needs to be shown.
 575   if (params->window_action == NavigateParams::NO_ACTION &&
 576       source_browser != params->browser &&
 577       params->browser->tab_strip_model()->empty()) {
 578     params->window_action = NavigateParams::SHOW_WINDOW;
 579   }
 580
 581   // If we create a popup window from a non user-gesture, don't activate it.
 582   if (params->window_action == NavigateParams::SHOW_WINDOW &&
 583       params->disposition == NEW_POPUP &&
 584       params->user_gesture == false) {
 585     params->window_action = NavigateParams::SHOW_WINDOW_INACTIVE;
 586   }
 587
 588   // Determine if the navigation was user initiated. If it was, we need to
 589   // inform the target WebContents, and we may need to update the UI.
 590   ui::PageTransition base_transition =
 591       ui::PageTransitionStripQualifier(params->transition);
 592   bool user_initiated =
 593       params->transition & ui::PAGE_TRANSITION_FROM_ADDRESS_BAR ||
 594       base_transition == ui::PAGE_TRANSITION_TYPED ||
 595       base_transition == ui::PAGE_TRANSITION_AUTO_BOOKMARK ||
 596       base_transition == ui::PAGE_TRANSITION_GENERATED ||
 597       base_transition == ui::PAGE_TRANSITION_AUTO_TOPLEVEL ||
 598       base_transition == ui::PAGE_TRANSITION_RELOAD ||
 599       base_transition == ui::PAGE_TRANSITION_KEYWORD;
 600
 601   // Check if this is a singleton tab that already exists
 602   int singleton_index = chrome::GetIndexOfSingletonTab(params);
 603
 604   // Did we use a prerender?
 605   bool swapped_in_prerender = false;
 606
 607   // If no target WebContents was specified, we need to construct one if
 608   // we are supposed to target a new tab; unless it's a singleton that already
 609   // exists.
 610   if (!params->target_contents && singleton_index < 0) {
 611     DCHECK(!params->url.is_empty());
 612     if (params->disposition != CURRENT_TAB) {
 613       params->target_contents = CreateTargetContents(*params, params->url);
 614
 615       // This function takes ownership of |params->target_contents| until it
 616       // is added to a TabStripModel.
 617       target_contents_owner.TakeOwnership();
 618     } else {
 619       // ... otherwise if we're loading in the current tab, the target is the
 620       // same as the source.
 621       DCHECK(params->source_contents);
 622       params->target_contents = params->source_contents;
 623
 624       // Prerender can only swap in CURRENT_TAB navigations; others have
 625       // different sessionStorage namespaces.
 626       swapped_in_prerender = SwapInPrerender(params->url, params);
 627     }
 628
 629     if (user_initiated)
 630       params->target_contents->UserGestureDone();
 631
 632     if (!swapped_in_prerender) {
 633       // Try to handle non-navigational URLs that popup dialogs and such, these
 634       // should not actually navigate.
 635       if (!HandleNonNavigationAboutURL(params->url)) {
 636         // Perform the actual navigation, tracking whether it came from the
 637         // renderer.
 638
 639         LoadURLInContents(params->target_contents, params->url, params);
 640       }
 641     }
 642   } else {
 643     // |target_contents| was specified non-NULL, and so we assume it has already
 644     // been navigated appropriately. We need to do nothing more other than
 645     // add it to the appropriate tabstrip.
 646   }
 647
 648   // If the user navigated from the omnibox, and the selected tab is going to
 649   // lose focus, then make sure the focus for the source tab goes away from the
 650   // omnibox.
 651   if (params->source_contents &&
 652       (params->disposition == NEW_FOREGROUND_TAB ||
 653        params->disposition == NEW_WINDOW) &&
 654       (params->tabstrip_add_types & TabStripModel::ADD_INHERIT_OPENER))
 655     params->source_contents->Focus();
 656
 657   if (params->source_contents == params->target_contents ||
 658       (swapped_in_prerender && params->disposition == CURRENT_TAB)) {
 659     // The navigation occurred in the source tab.
 660     params->browser->UpdateUIForNavigationInTab(params->target_contents,
 661                                                 params->transition,
 662                                                 user_initiated);
 663   } else if (singleton_index == -1) {
 664     // If some non-default value is set for the index, we should tell the
 665     // TabStripModel to respect it.
 666     if (params->tabstrip_index != -1)
 667       params->tabstrip_add_types |= TabStripModel::ADD_FORCE_INDEX;
 668
 669     // The navigation should insert a new tab into the target Browser.
 670     params->browser->tab_strip_model()->AddWebContents(
 671         params->target_contents,
 672         params->tabstrip_index,
 673         params->transition,
 674         params->tabstrip_add_types);
 675     // Now that the |params->target_contents| is safely owned by the target
 676     // Browser's TabStripModel, we can release ownership.
 677     target_contents_owner.ReleaseOwnership();
 678   }
 679
 680   if (singleton_index >= 0) {
 681     WebContents* target =
 682         params->browser->tab_strip_model()->GetWebContentsAt(singleton_index);
 683
 684     if (target->IsCrashed()) {
 685       target->GetController().Reload(true);
 686     } else if (params->path_behavior == NavigateParams::IGNORE_AND_NAVIGATE &&
 687         target->GetURL() != params->url) {
 688       LoadURLInContents(target, params->url, params);
 689     }
 690
 691     // If the singleton tab isn't already selected, select it.
 692     if (params->source_contents != params->target_contents) {
 693       params->browser->tab_strip_model()->ActivateTabAt(singleton_index,
 694                                                         user_initiated);
 695     }
 696   }
 697
 698   if (params->disposition != CURRENT_TAB) {
 699     content::NotificationService::current()->Notify(
 700         chrome::NOTIFICATION_TAB_ADDED,
 701         content::Source<content::WebContentsDelegate>(params->browser),
 702         content::Details<WebContents>(params->target_contents));
 703   }
 704 }
 705
 706 bool IsURLAllowedInIncognito(const GURL& url,
 707                              content::BrowserContext* browser_context) {
 708   if (url.scheme() == content::kViewSourceScheme) {
 709     // A view-source URL is allowed in incognito mode only if the URL itself
 710     // is allowed in incognito mode. Remove the "view-source:" from the start
 711     // of the URL and validate the rest.
 712     std::string stripped_spec = url.spec();
 713     DCHECK_GT(stripped_spec.size(), strlen(content::kViewSourceScheme));
 714     stripped_spec.erase(0, strlen(content::kViewSourceScheme) + 1);
 715     GURL stripped_url(stripped_spec);
 716     return stripped_url.is_valid() &&
 717         IsURLAllowedInIncognito(stripped_url, browser_context);
 718   }
 719   // Most URLs are allowed in incognito; the following are exceptions.
 720   // chrome://extensions is on the list because it redirects to
 721   // chrome://settings.
 722   if (url.scheme() == content::kChromeUIScheme &&
 723       (url.host() == chrome::kChromeUISettingsHost ||
 724        url.host() == chrome::kChromeUISettingsFrameHost ||
 725        url.host() == chrome::kChromeUIHelpHost ||
 726        url.host() == chrome::kChromeUIExtensionsHost ||
 727        url.host() == chrome::kChromeUIBookmarksHost ||
 728 #if !defined(OS_CHROMEOS)
 729        url.host() == chrome::kChromeUIChromeSigninHost ||
 730 #endif
 731        url.host() == chrome::kChromeUIUberHost ||
 732        url.host() == chrome::kChromeUIThumbnailHost ||
 733        url.host() == chrome::kChromeUIThumbnailHost2 ||
 734        url.host() == chrome::kChromeUIThumbnailListHost ||
 735        url.host() == chrome::kChromeUISuggestionsHost ||
 736        url.host() == chrome::kChromeUIDevicesHost ||
 737        url.host() == chrome::kChromeUIVoiceSearchHost)) {
 738     return false;
 739   }
 740
 741   if (url.scheme() == chrome::kChromeSearchScheme &&
 742       (url.host() == chrome::kChromeUIThumbnailHost ||
 743        url.host() == chrome::kChromeUIThumbnailHost2 ||
 744        url.host() == chrome::kChromeUIThumbnailListHost ||
 745        url.host() == chrome::kChromeUISuggestionsHost)) {
 746     return false;
 747   }
 748
 749   GURL rewritten_url = url;
 750   bool reverse_on_redirect = false;
 751   content::BrowserURLHandler::GetInstance()->RewriteURLIfNecessary(
 752       &rewritten_url, browser_context, &reverse_on_redirect);
 753
 754   // Some URLs are mapped to uber subpages. Do not allow them in incognito.
 755   return !(rewritten_url.scheme() == content::kChromeUIScheme &&
 756            rewritten_url.host() == chrome::kChromeUIUberHost);
 757 }
 758
 759 }  // namespace chrome