Get rid of content::NavigationController in cc file and use "using" instead.

chrome/browser/extensions/extension_navigation_observer.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/extensions/extension_navigation_observer.h"
 
 #include "chrome/browser/extensions/extension_service.h"
 #include "chrome/browser/profiles/profile.h"
 #include "content/public/browser/navigation_controller.h"
 #include "content/public/browser/navigation_entry.h"
 #include "content/public/browser/notification_service.h"
 
+using content::NavigationController;
 using content::NavigationEntry;
 
 ExtensionNavigationObserver::ExtensionNavigationObserver(Profile* profile)
     : profile_(profile) {
   RegisterForNotifications();
 }
 
 ExtensionNavigationObserver::~ExtensionNavigationObserver() {}
 
 void ExtensionNavigationObserver::Observe(
     int type,
     const content::NotificationSource& source,
     const content::NotificationDetails& details) {
   if (type != content::NOTIFICATION_NAV_ENTRY_COMMITTED) {
     NOTREACHED();
     return;
   }
 
-  content::NavigationController* controller =
-      content::Source<content::NavigationController>(source).ptr();
+  NavigationController* controller =
+      content::Source<NavigationController>(source).ptr();
   if (!profile_->IsSameProfile(
           Profile::FromBrowserContext(controller->GetBrowserContext())))
     return;
 
   PromptToEnableExtensionIfNecessary(controller);
 }
 
 void ExtensionNavigationObserver::RegisterForNotifications() {
   registrar_.Add(this, content::NOTIFICATION_NAV_ENTRY_COMMITTED,
                  content::NotificationService::AllSources());
 }
 
 void ExtensionNavigationObserver::PromptToEnableExtensionIfNecessary(
-    content::NavigationController* nav_controller) {
+    NavigationController* nav_controller) {
   // Bail out if we're already running a prompt.
   if (!in_progress_prompt_extension_id_.empty())
     return;
 
   NavigationEntry* nav_entry = nav_controller->GetActiveEntry();
   if (!nav_entry)
     return;
 
   ExtensionService* extension_service = profile_->GetExtensionService();
   const Extension* extension =
@@ skipping 16 matching lines @@
 
     extension_install_ui_.reset(new ExtensionInstallUI(profile_));
     extension_install_ui_->ConfirmReEnable(this, extension);
   }
 }
 
 void ExtensionNavigationObserver::InstallUIProceed() {
   ExtensionService* extension_service = profile_->GetExtensionService();
   const Extension* extension = extension_service->GetExtensionById(
       in_progress_prompt_extension_id_, true);
-  content::NavigationController* nav_controller =
+  NavigationController* nav_controller =
       in_progress_prompt_navigation_controller_;
   CHECK(extension);
   CHECK(nav_controller);
 
   in_progress_prompt_extension_id_ = "";
   in_progress_prompt_navigation_controller_ = NULL;
   extension_install_ui_.reset();
 
   // Grant permissions, re-enable the extension, and then reload the tab.
   extension_service->GrantPermissionsAndEnableExtension(extension);
   nav_controller->Reload(true);
 }
 
 void ExtensionNavigationObserver::InstallUIAbort(bool user_initiated) {
   ExtensionService* extension_service = profile_->GetExtensionService();
   const Extension* extension = extension_service->GetExtensionById(
       in_progress_prompt_extension_id_, true);
 
   in_progress_prompt_extension_id_ = "";
   in_progress_prompt_navigation_controller_ = NULL;
   extension_install_ui_.reset();
 
   std::string histogram_name = user_initiated ?
       "Extensions.Permissions_ReEnableCancel" :
       "Extensions.Permissions_ReEnableAbort";
   ExtensionService::RecordPermissionMessagesHistogram(
       extension, histogram_name.c_str());
 }