Don't destroy RenderWidgetCompositor during DoDeferredClose

content/renderer/gpu/render_widget_compositor.h

Index: content/renderer/gpu/render_widget_compositor.h
diff --git a/content/renderer/gpu/render_widget_compositor.h b/content/renderer/gpu/render_widget_compositor.h
index fc8d60ed9af4395661045928ef1efd09e0d700e4..104969daf73fca12deb4de4e70446d48340dc6e3 100644
--- a/content/renderer/gpu/render_widget_compositor.h
+++ b/content/renderer/gpu/render_widget_compositor.h
@@ -75,6 +75,7 @@ class RenderWidgetCompositor : public blink::WebLayerTreeView,
       scoped_ptr<base::Value> value,
       const base::Callback<void(scoped_ptr<base::Value>)>& callback);
   bool SendMessageToMicroBenchmark(int id, scoped_ptr<base::Value> value);
+  void Shutdown();
 
   // WebLayerTreeView implementation.
   virtual void setSurfaceReady();