NOT YET READY: Improve granularity of window namespaces in Blink.

extensions/renderer/extension_frame_helper.h

Index: extensions/renderer/extension_frame_helper.h
diff --git a/extensions/renderer/extension_frame_helper.h b/extensions/renderer/extension_frame_helper.h
index d4fc8d6ad21e885f6c9ce21f9c48597acdaa8bad..9d95c6f683dee2d4f1fa230e0bce9c460bb69305 100644
--- a/extensions/renderer/extension_frame_helper.h
+++ b/extensions/renderer/extension_frame_helper.h
@@ -52,6 +52,11 @@ class ExtensionFrameHelper
   static content::RenderFrame* GetBackgroundPageFrame(
       const std::string& extension_id);
 
+  // Finds a frame with the given |name|.
+  static content::RenderFrame* FindFrame(
+      content::RenderFrame* relative_to_frame,
+      const std::string& name);
+
   // Returns true if the given |context| is for any frame in the extension's
   // event page.
   // TODO(devlin): This isn't really used properly, and should probably be