Get rid of extensions dependency from content\browser.

chrome/browser/sync/glue/session_change_processor.cc

 // Copyright (c) 2011 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 "chrome/browser/sync/glue/session_change_processor.h"
 
 #include <sstream>
 #include <string>
 #include <vector>
 
 #include "base/logging.h"
 #include "base/memory/scoped_vector.h"
+#include "chrome/browser/extensions/extension_tab_helper.h"
 #include "chrome/browser/profiles/profile.h"
 #include "chrome/browser/sync/engine/syncapi.h"
 #include "chrome/browser/sync/glue/session_model_associator.h"
 #include "chrome/browser/sync/profile_sync_service.h"
 #include "content/browser/tab_contents/navigation_controller.h"
 #include "content/browser/tab_contents/tab_contents.h"
 #include "content/common/notification_details.h"
 #include "content/common/notification_service.h"
 #include "content/common/notification_source.h"
 
@@ skipping 95 matching lines @@
       NavigationController* controller =
           Source<NavigationController>(source).ptr();
       if (controller->profile() != profile_) {
         return;
       }
       modified_tabs.push_back(controller->tab_contents());
       break;
     }
 
     case NotificationType::TAB_CONTENTS_APPLICATION_EXTENSION_CHANGED: {
-      TabContents* tab_contents = Source<TabContents>(source).ptr();
-      DCHECK(tab_contents);
-      if (tab_contents->profile() != profile_) {
+      ExtensionTabHelper* extension_tab_helper =
+          Source<ExtensionTabHelper>(source).ptr();
+      if (extension_tab_helper->tab_contents()->profile() != profile_) {
         return;
       }
-      if (tab_contents->extension_app()) {
-        modified_tabs.push_back(tab_contents);
+      if (extension_tab_helper->extension_app()) {
+        modified_tabs.push_back(extension_tab_helper->tab_contents());
       }
       break;
     }
     default:
       LOG(ERROR) << "Received unexpected notification of type "
                   << type.value;
       break;
   }
 
   // Associate windows first to ensure tabs have homes.
@@ skipping 111 matching lines @@
       NotificationService::AllSources());
 }
 
 void SessionChangeProcessor::StopObserving() {
   DCHECK(BrowserThread::CurrentlyOn(BrowserThread::UI));
   DCHECK(profile_);
   notification_registrar_.RemoveAll();
 }
 
 }  // namespace browser_sync