Stop disabling force_compositing_mode for background RenderViews.

chrome/browser/extensions/extension_webkit_preferences.cc

 // 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.
 
 #include "chrome/browser/extensions/extension_webkit_preferences.h"
 
 #include "base/command_line.h"
 #include "chrome/common/chrome_switches.h"
 #include "extensions/common/extension.h"
 #include "extensions/common/manifest.h"
 #include "webkit/common/webpreferences.h"
 
 namespace extension_webkit_preferences {
 
 void SetPreferences(const extensions::Extension* extension,
                     extensions::ViewType render_view_type,
                     WebPreferences* webkit_prefs) {
   if (!extension)
     return;
 
   if (!extension->is_hosted_app()) {
     // Extensions are trusted so we override any user preferences for disabling
     // javascript or images.
     webkit_prefs->loads_images_automatically = true;
     webkit_prefs->javascript_enabled = true;
 
     // Tabs aren't typically allowed to close windows. But extensions shouldn't
     // be subject to that.
     webkit_prefs->allow_scripts_to_close_windows = true;
-
-    // Disable gpu acceleration for extension background pages to avoid
-    // unecessarily creating a compositor context for them.
-    if (render_view_type == extensions::VIEW_TYPE_EXTENSION_BACKGROUND_PAGE) {
-      webkit_prefs->accelerated_compositing_enabled = false;
-      webkit_prefs->force_compositing_mode = false;
-    }
   }
 
   if (extension->is_platform_app()) {
     webkit_prefs->databases_enabled = false;
     webkit_prefs->local_storage_enabled = false;
     webkit_prefs->sync_xhr_in_documents_enabled = false;
     webkit_prefs->cookie_enabled = false;
   }
 
   // Enable WebGL features that regular pages can't access, since they add
   // more risk of fingerprinting.
   webkit_prefs->privileged_webgl_extensions_enabled = true;
 }
 
 }  // namespace extension_webkit_preferences