[Extensions] Fix improper extension tab ownership bug

extensions/browser/extension_web_contents_observer.cc

 // Copyright 2014 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #include "extensions/browser/extension_web_contents_observer.h"
 
 #include "content/public/browser/child_process_security_policy.h"
 #include "content/public/browser/render_frame_host.h"
 #include "content/public/browser/render_process_host.h"
 #include "content/public/browser/render_view_host.h"
@@ skipping 43 matching lines @@
       render_frame_host->GetRoutingID(), GetViewType(web_contents())));
 
   const Extension* frame_extension = GetExtensionFromFrame(render_frame_host);
   if (frame_extension) {
     ExtensionsBrowserClient::Get()->RegisterMojoServices(render_frame_host,
                                                          frame_extension);
     ProcessManager::Get(browser_context_)
         ->RegisterRenderFrameHost(web_contents(), render_frame_host,
                                   frame_extension);
   }
-
-  // This can be different from |frame_extension| above in the case of, e.g.,
-  // a non-extension iframe hosted in a chrome-extension:// page.
-  const Extension* main_frame_extension =
-      GetExtensionFromFrame(web_contents()->GetMainFrame());
-  // We notify the render frame that it's in an extension's tab, but not if this
-  // is a hosted app (we don't mind scripting on hosted apps' pages).
-  if (main_frame_extension && !main_frame_extension->is_hosted_app()) {
-    render_frame_host->Send(new ExtensionMsg_SetMainFrameExtensionOwner(
-        render_frame_host->GetRoutingID(), main_frame_extension->id()));
-  }
 }
 
 content::WebContents* ExtensionWebContentsObserver::GetAssociatedWebContents()
     const {
   return web_contents();
 }
 
 void ExtensionWebContentsObserver::RenderViewCreated(
     content::RenderViewHost* render_view_host) {
   // TODO(devlin): Most/all of this should move to RenderFrameCreated.
@@ skipping 134 matching lines @@
   // Since this is called for all existing RenderFrameHosts during the
   // ExtensionWebContentsObserver's creation, it's possible that not all hosts
   // are ready.
   // We only initialize the frame if the renderer counterpart is live; otherwise
   // we wait for the RenderFrameCreated notification.
   if (render_frame_host->IsRenderFrameLive())
     InitializeRenderFrame(render_frame_host);
 }
 
 }  // namespace extensions