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

chrome/browser/errorpage_browsertest.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 "base/bind.h"
 #include "base/utf_string_conversions.h"
 #include "chrome/browser/net/url_request_mock_util.h"
 #include "chrome/browser/ui/browser.h"
 #include "chrome/browser/ui/tab_contents/tab_contents_wrapper.h"
 #include "chrome/test/base/in_process_browser_test.h"
 #include "chrome/test/base/ui_test_utils.h"
 #include "content/browser/net/url_request_failed_dns_job.h"
 #include "content/browser/net/url_request_mock_http_job.h"
 #include "content/browser/tab_contents/tab_contents.h"
 #include "content/test/test_navigation_observer.h"
 
 using content::BrowserThread;
+using content::NavigationController;
 
 class ErrorPageTest : public InProcessBrowserTest {
  public:
   enum HistoryNavigationDirection {
     HISTORY_NAVIGATE_BACK,
     HISTORY_NAVIGATE_FORWARD,
   };
 
   // Navigates the active tab to a mock url created for the file at |file_path|.
   void NavigateToFileURL(const FilePath::StringType& file_path) {
@@ skipping 46 matching lines @@
   // Navigates the browser the indicated direction in the history and waits for
   // |num_navigations| to occur and the title to change to |expected_title|.
   void NavigateHistoryAndWaitForTitle(const std::string& expected_title,
                                       int num_navigations,
                                       HistoryNavigationDirection direction) {
     ui_test_utils::TitleWatcher title_watcher(
         browser()->GetSelectedWebContents(),
         ASCIIToUTF16(expected_title));
 
     TestNavigationObserver test_navigation_observer(
-      content::Source<content::NavigationController>(
+      content::Source<NavigationController>(
             &browser()->GetSelectedTabContentsWrapper()->tab_contents()->
                 GetController()),
         NULL,
         num_navigations);
     if (direction == HISTORY_NAVIGATE_BACK) {
       browser()->GoBack(CURRENT_TAB);
     } else if (direction == HISTORY_NAVIGATE_FORWARD) {
       browser()->GoForward(CURRENT_TAB);
     } else {
       FAIL();
@@ skipping 95 matching lines @@
 }
 
 // Checks that the Link Doctor is not loaded when we receive an actual 404 page.
 IN_PROC_BROWSER_TEST_F(ErrorPageTest, Page404) {
   NavigateToURLAndWaitForTitle(
       URLRequestMockHTTPJob::GetMockUrl(
           FilePath(FILE_PATH_LITERAL("page404.html"))),
       "SUCCESS",
       1);
 }