Stop disabling force_compositing_mode for background RenderViews.

content/public/browser/content_browser_client.h

 // Copyright (c) 2012 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_PUBLIC_BROWSER_CONTENT_BROWSER_CLIENT_H_
 #define CONTENT_PUBLIC_BROWSER_CONTENT_BROWSER_CLIENT_H_
 
 #include <map>
 #include <string>
 #include <utility>
@@ skipping 502 matching lines @@
 
   // Getters for common objects.
   virtual net::NetLog* GetNetLog();
 
   // Creates a new AccessTokenStore for gelocation.
   virtual AccessTokenStore* CreateAccessTokenStore();
 
   // Returns true if fast shutdown is possible.
   virtual bool IsFastShutdownPossible();
 
+  // Returns true if the view runs in the background and is never visible.
+  virtual bool IsRenderViewHostForBackground(RenderViewHost* render_view_host);

[jam, 2014/04/10 20:27:48]

nit: content doesn't know about "background" concept, that's an extensions
feature. so maybe call this IsRenderViewHostNeverVisible or something similar?

[danakj, 2014/04/10 20:37:12]

Done.

+
   // Called by WebContents to override the WebKit preferences that are used by
   // the renderer. The content layer will add its own settings, and then it's up
   // to the embedder to update it if it wants.
   virtual void OverrideWebkitPrefs(RenderViewHost* render_view_host,
                                    const GURL& url,
                                    WebPreferences* prefs) {}
 
   // Inspector setting was changed and should be persisted.
   virtual void UpdateInspectorSetting(RenderViewHost* rvh,
                                       const std::string& key,
@@ skipping 110 matching lines @@
   // Returns a special cookie store to use for a given render process, or NULL
   // if the default cookie store should be used
   // This is called on the IO thread.
   virtual net::CookieStore* OverrideCookieStoreForRenderProcess(
       int render_process_id_);
 };
 
 }  // namespace content
 
 #endif  // CONTENT_PUBLIC_BROWSER_CONTENT_BROWSER_CLIENT_H_