Add abstractions that let embedders drive tests of WebContents.

chrome/browser/extensions/extension_tab_util.h

 // Copyright (c) 2012 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.
 
 #ifndef CHROME_BROWSER_EXTENSIONS_EXTENSION_TAB_UTIL_H__
 #define CHROME_BROWSER_EXTENSIONS_EXTENSION_TAB_UTIL_H__
 #pragma once
 
 #include <string>
 
 class Browser;
 class Profile;
-class TabContents;
 class TabContentsWrapper;
 class TabStripModel;
 
 namespace base {
 class DictionaryValue;
 class ListValue;
 }
 
 namespace content {
 class WebContents;
@@ skipping 34 matching lines @@
   // Any out parameter (|browser|, |tab_strip|, |contents|, & |tab_index|) may
   // be NULL and will not be set within the function.
   static bool GetTabById(int tab_id, Profile* profile, bool incognito_enabled,
                          Browser** browser,
                          TabStripModel** tab_strip,
                          TabContentsWrapper** contents,
                          int* tab_index);
 };
 
 #endif  // CHROME_BROWSER_EXTENSIONS_EXTENSION_TAB_UTIL_H__