cc: Add initial GPU-to-GPU copy rasterizer implementation.

content/renderer/render_thread_impl.h

Index: content/renderer/render_thread_impl.h
diff --git a/content/renderer/render_thread_impl.h b/content/renderer/render_thread_impl.h
index 4c945b1f971141ac37b3affc4fb0318dd6c390b6..de75085decd21fbb210b62b162153f124434c865 100644
--- a/content/renderer/render_thread_impl.h
+++ b/content/renderer/render_thread_impl.h
@@ -218,6 +218,8 @@ class CONTENT_EXPORT RenderThreadImpl : public RenderThread,
 
   bool is_map_image_enabled() const { return is_map_image_enabled_; }
 
+  bool is_zero_copy_enabled() const { return is_zero_copy_enabled_; }
+
   AppCacheDispatcher* appcache_dispatcher() const {
     return appcache_dispatcher_.get();
   }
@@ -541,6 +543,7 @@ class CONTENT_EXPORT RenderThreadImpl : public RenderThread,
   bool is_low_res_tiling_enabled_;
   bool is_lcd_text_enabled_;
   bool is_map_image_enabled_;
+  bool is_zero_copy_enabled_;
 
   DISALLOW_COPY_AND_ASSIGN(RenderThreadImpl);
 };