components/plugins/renderer/loadable_plugin_placeholder.cc

   1 // Copyright 2015 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 "components/plugins/renderer/loadable_plugin_placeholder.h"
   6
   7 #include "base/bind.h"
   8 #include "base/bind_helpers.h"
   9 #include "base/command_line.h"
  10 #include "base/json/string_escape.h"
  11 #include "base/strings/string_piece.h"
  12 #include "base/strings/utf_string_conversions.h"
  13 #include "base/thread_task_runner_handle.h"
  14 #include "base/values.h"
  15 #include "content/public/child/v8_value_converter.h"
  16 #include "content/public/common/content_switches.h"
  17 #include "content/public/renderer/render_frame.h"
  18 #include "content/public/renderer/render_thread.h"
  19 #include "gin/handle.h"
  20 #include "gin/object_template_builder.h"
  21 #include "third_party/WebKit/public/web/WebDOMMessageEvent.h"
  22 #include "third_party/WebKit/public/web/WebDocument.h"
  23 #include "third_party/WebKit/public/web/WebElement.h"
  24 #include "third_party/WebKit/public/web/WebInputEvent.h"
  25 #include "third_party/WebKit/public/web/WebKit.h"
  26 #include "third_party/WebKit/public/web/WebLocalFrame.h"
  27 #include "third_party/WebKit/public/web/WebPluginContainer.h"
  28 #include "third_party/WebKit/public/web/WebScriptSource.h"
  29 #include "third_party/WebKit/public/web/WebSerializedScriptValue.h"
  30 #include "third_party/WebKit/public/web/WebView.h"
  31
  32 using base::UserMetricsAction;
  33 using content::PluginInstanceThrottler;
  34 using content::RenderThread;
  35
  36 namespace plugins {
  37
  38 // TODO(tommycli): After an unthrottling size update, re-check the size after
  39 // this delay, as Blink can report incorrect sizes to plugins while the
  40 // compositing state is dirty. Chosen because it seems to work.
  41 const int kSizeChangeRecheckDelayMilliseconds = 100;
  42
  43 void LoadablePluginPlaceholder::BlockForPowerSaverPoster() {
  44   DCHECK(!is_blocked_for_power_saver_poster_);
  45   is_blocked_for_power_saver_poster_ = true;
  46
  47   render_frame()->RegisterPeripheralPlugin(
  48       GURL(GetPluginParams().url).GetOrigin(),
  49       base::Bind(&LoadablePluginPlaceholder::MarkPluginEssential,
  50                  weak_factory_.GetWeakPtr(),
  51                  PluginInstanceThrottler::UNTHROTTLE_METHOD_BY_WHITELIST));
  52 }
  53
  54 void LoadablePluginPlaceholder::SetPremadePlugin(
  55     content::PluginInstanceThrottler* throttler) {
  56   DCHECK(throttler);
  57   DCHECK(!premade_throttler_);
  58   premade_throttler_ = throttler;
  59 }
  60
  61 LoadablePluginPlaceholder::LoadablePluginPlaceholder(
  62     content::RenderFrame* render_frame,
  63     blink::WebLocalFrame* frame,
  64     const blink::WebPluginParams& params,
  65     const std::string& html_data)
  66     : PluginPlaceholderBase(render_frame, frame, params, html_data),
  67       is_blocked_for_background_tab_(false),
  68       is_blocked_for_prerendering_(false),
  69       is_blocked_for_power_saver_poster_(false),
  70       power_saver_enabled_(false),
  71       premade_throttler_(nullptr),
  72       allow_loading_(true),
  73       finished_loading_(false),
  74       in_size_recheck_(false),
  75       weak_factory_(this) {
  76 }
  77
  78 LoadablePluginPlaceholder::~LoadablePluginPlaceholder() {
  79 }
  80
  81 void LoadablePluginPlaceholder::MarkPluginEssential(
  82     PluginInstanceThrottler::PowerSaverUnthrottleMethod method) {
  83   if (!power_saver_enabled_)
  84     return;
  85
  86   power_saver_enabled_ = false;
  87
  88   if (premade_throttler_)
  89     premade_throttler_->MarkPluginEssential(method);
  90   else
  91     PluginInstanceThrottler::RecordUnthrottleMethodMetric(method);
  92
  93   if (is_blocked_for_power_saver_poster_) {
  94     is_blocked_for_power_saver_poster_ = false;
  95     if (!LoadingBlocked())
  96       LoadPlugin();
  97   }
  98 }
  99
 100 void LoadablePluginPlaceholder::ReplacePlugin(blink::WebPlugin* new_plugin) {
 101   CHECK(plugin());
 102   if (!new_plugin)
 103     return;
 104   blink::WebPluginContainer* container = plugin()->container();
 105   // Set the new plugin on the container before initializing it.
 106   container->setPlugin(new_plugin);
 107   // Save the element in case the plugin is removed from the page during
 108   // initialization.
 109   blink::WebElement element = container->element();
 110   bool plugin_needs_initialization =
 111       !premade_throttler_ || new_plugin != premade_throttler_->GetWebPlugin();
 112   if (plugin_needs_initialization && !new_plugin->initialize(container)) {
 113     // We couldn't initialize the new plugin. Restore the old one and abort.
 114     container->setPlugin(plugin());
 115     return;
 116   }
 117
 118   // The plugin has been removed from the page. Destroy the old plugin. We
 119   // will be destroyed as soon as V8 garbage collects us.
 120   if (!element.pluginContainer()) {
 121     plugin()->destroy();
 122     return;
 123   }
 124
 125   // During initialization, the new plugin might have replaced itself in turn
 126   // with another plugin. Make sure not to use the passed in |new_plugin| after
 127   // this point.
 128   new_plugin = container->plugin();
 129
 130   plugin()->RestoreTitleText();
 131   container->invalidate();
 132   container->reportGeometry();
 133   plugin()->ReplayReceivedData(new_plugin);
 134   plugin()->destroy();
 135 }
 136
 137 void LoadablePluginPlaceholder::SetMessage(const base::string16& message) {
 138   message_ = message;
 139   if (finished_loading_)
 140     UpdateMessage();
 141 }
 142
 143 void LoadablePluginPlaceholder::UpdateMessage() {
 144   if (!plugin())
 145     return;
 146   std::string script =
 147       "window.setMessage(" + base::GetQuotedJSONString(message_) + ")";
 148   plugin()->web_view()->mainFrame()->executeScript(
 149       blink::WebScriptSource(base::UTF8ToUTF16(script)));
 150 }
 151
 152 void LoadablePluginPlaceholder::PluginDestroyed() {
 153   if (power_saver_enabled_) {
 154     if (premade_throttler_) {
 155       // Since the premade plugin has been detached from the container, it will
 156       // not be automatically destroyed along with the page.
 157       premade_throttler_->GetWebPlugin()->destroy();
 158       premade_throttler_ = nullptr;
 159     } else if (is_blocked_for_power_saver_poster_) {
 160       // Record the NEVER unthrottle count only if there is no throttler.
 161       PluginInstanceThrottler::RecordUnthrottleMethodMetric(
 162           PluginInstanceThrottler::UNTHROTTLE_METHOD_NEVER);
 163     }
 164
 165     // Prevent processing subsequent calls to MarkPluginEssential.
 166     power_saver_enabled_ = false;
 167   }
 168
 169   PluginPlaceholderBase::PluginDestroyed();
 170 }
 171
 172 v8::Local<v8::Object> LoadablePluginPlaceholder::GetV8ScriptableObject(
 173     v8::Isolate* isolate) const {
 174   // Pass through JavaScript access to the underlying throttled plugin.
 175   if (premade_throttler_ && premade_throttler_->GetWebPlugin()) {
 176     return premade_throttler_->GetWebPlugin()->v8ScriptableObject(isolate);
 177   }
 178   return v8::Local<v8::Object>();
 179 }
 180
 181 void LoadablePluginPlaceholder::OnUnobscuredSizeUpdate(
 182     const gfx::Size& unobscured_size) {
 183   DCHECK(
 184       content::RenderThread::Get()->GetTaskRunner()->BelongsToCurrentThread());
 185   if (!power_saver_enabled_ || !premade_throttler_ || !finished_loading_)
 186     return;
 187
 188   unobscured_size_ = unobscured_size;
 189
 190   // During a size recheck, we will get another notification into this method.
 191   // Use this flag to early exit to prevent reentrancy issues.
 192   if (in_size_recheck_)
 193     return;
 194
 195   if (PluginInstanceThrottler::IsLargeContent(unobscured_size.width(),
 196                                               unobscured_size.height())) {
 197     if (!size_update_timer_.IsRunning()) {
 198       // TODO(tommycli): We have to post a delayed task to recheck the size, as
 199       // Blink can report wrong sizes for partially obscured plugins while the
 200       // compositing state is dirty. https://crbug.com/343769
 201       size_update_timer_.Start(
 202           FROM_HERE, base::TimeDelta::FromMilliseconds(
 203                          kSizeChangeRecheckDelayMilliseconds),
 204           base::Bind(&LoadablePluginPlaceholder::RecheckSizeAndMaybeUnthrottle,
 205                      weak_factory_.GetWeakPtr()));
 206     }
 207   } else {
 208     // Cancel any pending unthrottle due to resize calls.
 209     size_update_timer_.Stop();
 210   }
 211 }
 212
 213 void LoadablePluginPlaceholder::WasShown() {
 214   if (is_blocked_for_background_tab_) {
 215     is_blocked_for_background_tab_ = false;
 216     if (!LoadingBlocked())
 217       LoadPlugin();
 218   }
 219 }
 220
 221 void LoadablePluginPlaceholder::OnLoadBlockedPlugins(
 222     const std::string& identifier) {
 223   if (!identifier.empty() && identifier != identifier_)
 224     return;
 225
 226   RenderThread::Get()->RecordAction(UserMetricsAction("Plugin_Load_UI"));
 227   LoadPlugin();
 228 }
 229
 230 void LoadablePluginPlaceholder::OnSetIsPrerendering(bool is_prerendering) {
 231   // Prerendering can only be enabled prior to a RenderView's first navigation,
 232   // so no BlockedPlugin should see the notification that enables prerendering.
 233   DCHECK(!is_prerendering);
 234   if (is_blocked_for_prerendering_) {
 235     is_blocked_for_prerendering_ = false;
 236     if (!LoadingBlocked())
 237       LoadPlugin();
 238   }
 239 }
 240
 241 void LoadablePluginPlaceholder::LoadPlugin() {
 242   // This is not strictly necessary but is an important defense in case the
 243   // event propagation changes between "close" vs. "click-to-play".
 244   if (hidden())
 245     return;
 246   if (!plugin())
 247     return;
 248   if (!allow_loading_) {
 249     NOTREACHED();
 250     return;
 251   }
 252
 253   if (premade_throttler_) {
 254     premade_throttler_->SetHiddenForPlaceholder(false /* hidden */);
 255     ReplacePlugin(premade_throttler_->GetWebPlugin());
 256     premade_throttler_ = nullptr;
 257   } else {
 258     ReplacePlugin(CreatePlugin());
 259   }
 260 }
 261
 262 void LoadablePluginPlaceholder::LoadCallback() {
 263   RenderThread::Get()->RecordAction(UserMetricsAction("Plugin_Load_Click"));
 264   // If the user specifically clicks on the plugin content's placeholder,
 265   // disable power saver throttling for this instance.
 266   MarkPluginEssential(PluginInstanceThrottler::UNTHROTTLE_METHOD_BY_CLICK);
 267   LoadPlugin();
 268 }
 269
 270 void LoadablePluginPlaceholder::DidFinishLoadingCallback() {
 271   finished_loading_ = true;
 272   if (message_.length() > 0)
 273     UpdateMessage();
 274
 275   // Wait for the placeholder to finish loading to hide the premade plugin.
 276   // This is necessary to prevent a flicker.
 277   if (premade_throttler_ && power_saver_enabled_)
 278     premade_throttler_->SetHiddenForPlaceholder(true /* hidden */);
 279
 280   // Set an attribute and post an event, so browser tests can wait for the
 281   // placeholder to be ready to receive simulated user input.
 282   if (base::CommandLine::ForCurrentProcess()->HasSwitch(
 283           switches::kEnablePluginPlaceholderTesting)) {
 284     blink::WebElement element = plugin()->container()->element();
 285     element.setAttribute("placeholderLoaded", "true");
 286
 287     scoped_ptr<content::V8ValueConverter> converter(
 288         content::V8ValueConverter::create());
 289     base::StringValue value("placeholderLoaded");
 290     blink::WebSerializedScriptValue message_data =
 291         blink::WebSerializedScriptValue::serialize(converter->ToV8Value(
 292             &value, element.document().frame()->mainWorldScriptContext()));
 293
 294     blink::WebDOMEvent event = element.document().createEvent("MessageEvent");
 295     blink::WebDOMMessageEvent msg_event = event.to<blink::WebDOMMessageEvent>();
 296     msg_event.initMessageEvent("message",     // type
 297                                false,         // canBubble
 298                                false,         // cancelable
 299                                message_data,  // data
 300                                "",            // origin [*]
 301                                NULL,          // source [*]
 302                                "");           // lastEventId
 303     element.dispatchEvent(msg_event);
 304   }
 305 }
 306
 307 void LoadablePluginPlaceholder::SetPluginInfo(
 308     const content::WebPluginInfo& plugin_info) {
 309   plugin_info_ = plugin_info;
 310 }
 311
 312 const content::WebPluginInfo& LoadablePluginPlaceholder::GetPluginInfo() const {
 313   return plugin_info_;
 314 }
 315
 316 void LoadablePluginPlaceholder::SetIdentifier(const std::string& identifier) {
 317   identifier_ = identifier;
 318 }
 319
 320 const std::string& LoadablePluginPlaceholder::GetIdentifier() const {
 321   return identifier_;
 322 }
 323
 324 bool LoadablePluginPlaceholder::LoadingBlocked() const {
 325   DCHECK(allow_loading_);
 326   return is_blocked_for_background_tab_ || is_blocked_for_power_saver_poster_ ||
 327          is_blocked_for_prerendering_;
 328 }
 329
 330 void LoadablePluginPlaceholder::RecheckSizeAndMaybeUnthrottle() {
 331   DCHECK(
 332       content::RenderThread::Get()->GetTaskRunner()->BelongsToCurrentThread());
 333   DCHECK(!in_size_recheck_);
 334
 335   if (!plugin())
 336     return;
 337
 338   in_size_recheck_ = true;
 339
 340   // Re-check the size in case the reported size was incorrect.
 341   plugin()->container()->reportGeometry();
 342
 343   if (PluginInstanceThrottler::IsLargeContent(unobscured_size_.width(),
 344                                               unobscured_size_.height())) {
 345     MarkPluginEssential(
 346         PluginInstanceThrottler::UNTHROTTLE_METHOD_BY_SIZE_CHANGE);
 347   }
 348
 349   in_size_recheck_ = false;
 350 }
 351
 352 }  // namespace plugins