Revert of Remove EnableThreadedCompositing from the browser.

content/renderer/render_widget.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_RENDERER_RENDER_WIDGET_H_
 #define CONTENT_RENDERER_RENDER_WIDGET_H_
 
 #include <deque>
 #include <map>
 
@@ skipping 641 matching lines @@
 
   // The device color profile on supported platforms.
   std::vector<char> device_color_profile_;
 
   // State associated with synthetic gestures. Synthetic gestures are processed
   // in-order, so a queue is sufficient to identify the correct state for a
   // completed gesture.
   std::queue<SyntheticGestureCompletionCallback>
       pending_synthetic_gesture_callbacks_;
 
+  // Specified whether the compositor will run in its own thread.
+  bool is_threaded_compositing_enabled_;
+
   const ui::LatencyInfo* current_event_latency_info_;
 
   uint32 next_output_surface_id_;
 
 #if defined(OS_ANDROID)
   // Indicates value in the focused text field is in dirty state, i.e. modified
   // by script etc., not by user input.
   bool text_field_is_dirty_;
 
   // A counter for number of outstanding messages from the renderer to the
@@ skipping 31 matching lines @@
 
   ui::MenuSourceType context_menu_source_type_;
   gfx::Point touch_editing_context_menu_location_;
 
   DISALLOW_COPY_AND_ASSIGN(RenderWidget);
 };
 
 }  // namespace content
 
 #endif  // CONTENT_RENDERER_RENDER_WIDGET_H_