Initialize and set compositor thread in WebKit initialization

content/renderer/render_thread.h

Index: content/renderer/render_thread.h
diff --git a/content/renderer/render_thread.h b/content/renderer/render_thread.h
index 3aacab51b88f5108651fbc3172fcd0be4ae73e69..ae13267f85f086cc61ee7b5c4a22bb03387016c0 100644
--- a/content/renderer/render_thread.h
+++ b/content/renderer/render_thread.h
@@ -62,6 +62,10 @@ namespace v8 {
 class Extension;
 }
 
+namespace webkit_glue {
+class WebThreadImpl;
+}
+
 // The RenderThreadBase is the minimal interface that a RenderView/Widget
 // expects from a render thread. The interface basically abstracts a way to send
 // and receive messages.
@@ -276,6 +280,8 @@ class CONTENT_EXPORT RenderThread : public RenderThreadBase,
   // Map of registered v8 extensions. The key is the extension name.
   std::set<std::string> v8_extensions_;
 
+  scoped_ptr<webkit_glue::WebThreadImpl> compositor_thread_;
+
   ObserverList<RenderProcessObserver> observers_;
 
   DISALLOW_COPY_AND_ASSIGN(RenderThread);