Plugin Power Saver: Do not always throttle plugins with posters.

content/renderer/pepper/plugin_power_saver_helper.h

 // Copyright 2014 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 CONTENT_RENDERER_PEPPER_PLUGIN_POWER_SAVER_HELPER_H_
 #define CONTENT_RENDERER_PEPPER_PLUGIN_POWER_SAVER_HELPER_H_
 
 #include <set>
 #include <vector>
 
 #include "base/callback.h"
 #include "content/common/content_export.h"
 #include "content/public/renderer/render_frame_observer.h"
 #include "url/origin.h"
 
 namespace blink {
 struct WebPluginParams;
 struct WebRect;
 }
 
 namespace content {
 
 class CONTENT_EXPORT PluginPowerSaverHelper : public RenderFrameObserver {
  public:
   explicit PluginPowerSaverHelper(RenderFrame* render_frame);
   ~PluginPowerSaverHelper() override;
 
-  // See RenderFrame for documentation.
-  void RegisterPeripheralPlugin(const url::Origin& content_origin,
-                                const base::Closure& unthrottle_callback);
+ private:
+  friend class RenderFrameImpl;
 
-  // Returns true if this plugin should have power saver enabled.
-  //
-  // Power Saver is enabled for plugin content that are cross-origin and
-  // heuristically determined to be not essential to the web page content.
-  //
-  // Plugin content is defined to be cross-origin when the plugin source's
-  // origin differs from the top level frame's origin. For example:
-  //  - Cross-origin:  a.com -> b.com/plugin.swf
-  //  - Cross-origin:  a.com -> b.com/iframe.html -> b.com/plugin.swf
-  //  - Same-origin:   a.com -> b.com/iframe-to-a.html -> a.com/plugin.swf
-  //
-  // |main_frame_origin| is the origin of the main frame.
-  //
-  // |content_origin| is the origin of the plugin content.
-  //
-  // |width| and |height| are zoom and device scale independent logical pixels.
-  //
-  // |cross_origin_main_content| may be NULL. It is set to true if the
-  // plugin content is cross-origin but still the "main attraction" of the page.
-  bool ShouldThrottleContent(const url::Origin& main_frame_origin,
-                             const url::Origin& content_origin,
-                             const std::string& plugin_module_name,
-                             int width,
-                             int height,
-                             bool* cross_origin_main_content) const;
-
-  // Whitelists a |content_origin| so its content will never be throttled in
-  // this RenderFrame. Whitelist is cleared by top level navigation.
-  void WhitelistContentOrigin(const url::Origin& content_origin);
-
- private:
   struct PeripheralPlugin {
     PeripheralPlugin(const url::Origin& content_origin,
                      const base::Closure& unthrottle_callback);
     ~PeripheralPlugin();
 
     url::Origin content_origin;
     base::Closure unthrottle_callback;
   };
 
   enum OverrideForTesting {
     Normal,
     Never,
     IgnoreList,
     Always
   };
 
+  // See RenderFrame for documentation.
+  void RegisterPeripheralPlugin(const url::Origin& content_origin,
+                                const base::Closure& unthrottle_callback);
+  bool ShouldThrottleContent(const url::Origin& main_frame_origin,
+                             const url::Origin& content_origin,
+                             const std::string& plugin_module_name,
+                             int width,
+                             int height,
+                             bool* cross_origin_main_content) const;
+  void WhitelistContentOrigin(const url::Origin& content_origin);
+
   // RenderFrameObserver implementation.
   void DidCommitProvisionalLoad(bool is_new_navigation,
                                 bool is_same_page_navigation) override;
   bool OnMessageReceived(const IPC::Message& message) override;
 
   void OnUpdatePluginContentOriginWhitelist(
       const std::set<url::Origin>& origin_whitelist);
 
   OverrideForTesting override_for_testing_;
 
   // Local copy of the whitelist for the entire tab.
   std::set<url::Origin> origin_whitelist_;
 
   // Set of peripheral plugins eligible to be unthrottled ex post facto.
   std::vector<PeripheralPlugin> peripheral_plugins_;
 
   DISALLOW_COPY_AND_ASSIGN(PluginPowerSaverHelper);
 };
 
 }  // namespace content
 
 #endif  // CONTENT_RENDERER_PEPPER_PLUGIN_POWER_SAVER_HELPER_H_