Send resize event when the screen info changes.

content/browser/renderer_host/render_widget_host_impl.h

Index: content/browser/renderer_host/render_widget_host_impl.h
diff --git a/content/browser/renderer_host/render_widget_host_impl.h b/content/browser/renderer_host/render_widget_host_impl.h
index ecd86c5259560b94e04614741226ea4bfab79d1e..1b95a255901f66a3cce842397617fea7c40c41c3 100644
--- a/content/browser/renderer_host/render_widget_host_impl.h
+++ b/content/browser/renderer_host/render_widget_host_impl.h
@@ -551,7 +551,7 @@ class CONTENT_EXPORT RenderWidgetHostImpl
 
   // Fills in the |resize_params| struct.
   // Returns |false| if the update is redundant, |true| otherwise.
-  bool GetResizeParams(ViewMsg_Resize_Params* resize_params);
+  bool GetResizeParams(ViewMsg_Resize_Params* resize_params) const;
 
   // Sets the |resize_params| that were sent to the renderer bundled with the
   // request to create a new RenderWidget.
@@ -565,6 +565,10 @@ class CONTENT_EXPORT RenderWidgetHostImpl
     return --in_flight_event_count_;
   }
 
+  // Update screen_info_ if needed.
+  // Returns whether screen_info_ was updated.
+  bool UpdateScreenInfo();
+
   // The View associated with the RenderViewHost. The lifetime of this object
   // is associated with the lifetime of the Render process. If the Renderer
   // crashes, its View is destroyed and this pointer becomes NULL, even though