Turning the threaded compositor into a runtime option. This CL

content/renderer/render_widget.h

 // Copyright (c) 2011 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_RENDER_WIDGET_H_
 #define CONTENT_RENDERER_RENDER_WIDGET_H_
 #pragma once
 
 #include <vector>
 
@@ skipping 305 matching lines @@
   virtual bool WillHandleMouseEvent(const WebKit::WebMouseEvent& event);
 
   // Called by OnHandleInputEvent() to notify subclasses that a mouse event was
   // just handled.
   virtual void DidHandleMouseEvent(const WebKit::WebMouseEvent& event) {}
 
   // Called by OnHandleInputEvent() to notify subclasses that a touch event was
   // just handled.
   virtual void DidHandleTouchEvent(const WebKit::WebTouchEvent& event) {}
 
+  // Should return true if the underlying WebWidget is responsible for
+  // the scheduling of compositing requests.
+  virtual bool WebWidgetHandlesCompositorScheduling() const;
+
   // Routing ID that allows us to communicate to the parent browser process
   // RenderWidgetHost. When MSG_ROUTING_NONE, no messages may be sent.
   int32 routing_id_;
 
   // We are responsible for destroying this object via its Close method.
   WebKit::WebWidget* webwidget_;
 
   // Set to the ID of the view that initiated creating this view, if any. When
   // the view was initiated by the browser (the common case), this will be
   // MSG_ROUTING_NONE. This is used in determining ownership when opening
@@ skipping 121 matching lines @@
   bool animation_task_posted_;
   bool invalidation_task_posted_;
 
   bool has_disable_gpu_vsync_switch_;
   base::TimeTicks last_do_deferred_update_time_;
 
   DISALLOW_COPY_AND_ASSIGN(RenderWidget);
 };
 
 #endif  // CONTENT_RENDERER_RENDER_WIDGET_H_