Plugin Power Saver: Unthrottle dynamically sized plugins correctly.

components/plugins/renderer/loadable_plugin_placeholder.h

 // Copyright 2015 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #ifndef COMPONENTS_PLUGINS_RENDERER_LOADABLE_PLUGIN_PLACEHOLDER_H_
 #define COMPONENTS_PLUGINS_RENDERER_LOADABLE_PLUGIN_PLACEHOLDER_H_
 
 #include "base/memory/weak_ptr.h"
 #include "components/plugins/renderer/plugin_placeholder.h"
 #include "content/public/common/webplugininfo.h"
@@ skipping 67 matching lines @@
 
   // gin::Wrappable method:
   gin::ObjectTemplateBuilder GetObjectTemplateBuilder(
       v8::Isolate* isolate) override;
 
  private:
   // WebViewPlugin::Delegate methods:
   void PluginDestroyed() override;
   v8::Local<v8::Object> GetV8ScriptableObject(
       v8::Isolate* isolate) const override;
+#if defined(ENABLE_PLUGINS)
+  void OnUnobscuredSizeUpdate(const gfx::Size& unobscured_size) override;
+#endif
 
   // RenderFrameObserver methods:
   void WasShown() override;
 
   // Javascript callbacks:
   void LoadCallback();
   void HideCallback();
   void DidFinishLoadingCallback();
 
   void UpdateMessage();
 
   bool LoadingBlocked() const;
+#if defined(ENABLE_PLUGINS)
+  void RecheckSizeAndMaybeUnthrottle();
+#endif
 
   // Plugin creation is embedder-specific.
   virtual blink::WebPlugin* CreatePlugin() = 0;
 
   content::WebPluginInfo plugin_info_;
 
   base::string16 message_;
 
   // True if the plugin load was deferred due to page being a background tab.
   // Plugin may be automatically loaded when the page is foregrounded.
@@ skipping 12 matching lines @@
 
   // When we load, uses this premade plugin instead of creating a new one.
   content::PluginInstanceThrottler* premade_throttler_;
 
   bool allow_loading_;
 
   bool hidden_;
   bool finished_loading_;
   std::string identifier_;
 
+  // Used to prevent re-entrancy during the size recheck for throttled plugins.
+  bool in_size_recheck_;
+  gfx::Size unobscured_size_;
+
+  // A separate weak factory so we can schedule, coalesce and cancel unthrottle
+  // calls due to plugin size updates.
+  base::WeakPtrFactory<LoadablePluginPlaceholder> size_update_weak_factory_;

[groby-ooo-7-16, 2015/06/05 23:03:45]

You can skip the WeakPtrFactory thing, and instead just store your callback in a
CancelableCallback.

[tommycli, 2015/06/06 01:23:22]

Delaying this change per offline discussion.

+
   base::WeakPtrFactory<LoadablePluginPlaceholder> weak_factory_;
 
   DISALLOW_COPY_AND_ASSIGN(LoadablePluginPlaceholder);
 };
 
 }  // namespace plugins
 
 #endif  // COMPONENTS_PLUGINS_RENDERER_LOADABLE_PLUGIN_PLACEHOLDER_H_