Extend the ToRenderFrameHost magic to FrameTreeNode* and Shell*

content/browser/resource_loading_browsertest.cc

 // Copyright 2015 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 <stdlib.h>
 
 #include "content/public/test/browser_test_utils.h"
 #include "content/public/test/content_browser_test.h"
 #include "content/public/test/content_browser_test_utils.h"
 #include "content/public/test/test_navigation_observer.h"
 #include "content/shell/browser/shell.h"
 
 namespace content {
 
 class ResourceLoadingBrowserTest : public ContentBrowserTest  {
 };
 
 const char kResourceLoadingNonMobilePage[] =
     "/resource_loading/resource_loading_non_mobile.html";
 
 IN_PROC_BROWSER_TEST_F(ResourceLoadingBrowserTest,
   ResourceLoadingAvoidDoubleDownloads) {
   ASSERT_TRUE(embedded_test_server()->Start());
   GURL url = embedded_test_server()->GetURL(kResourceLoadingNonMobilePage);
   NavigateToURL(shell(), url);
   int data = -1;
-  EXPECT_TRUE(ExecuteScriptAndExtractInt(shell()->web_contents(),
-    "getResourceNumber()", &data));
+  EXPECT_TRUE(
+      ExecuteScriptAndExtractInt(shell(), "getResourceNumber()", &data));
   EXPECT_EQ(2, data);
 }
 
 } // namespace content