Move Extension into extensions namespace

chrome/browser/extensions/extension_install_ui_browsertest.cc

 // 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.
 
 #include "base/string_util.h"
 #include "chrome/browser/extensions/extension_browsertest.h"
 #include "chrome/browser/extensions/extension_service.h"
 #include "chrome/browser/extensions/theme_installed_infobar_delegate.h"
 #include "chrome/browser/infobars/infobar_tab_helper.h"
 #include "chrome/browser/profiles/profile.h"
 #include "chrome/browser/ui/browser.h"
 #include "chrome/browser/ui/tab_contents/tab_contents_wrapper.h"
 #include "chrome/browser/ui/webui/ntp/new_tab_ui.h"
 #include "chrome/browser/themes/theme_service_factory.h"
 #include "chrome/test/base/ui_test_utils.h"
 #include "content/public/browser/web_contents.h"
 
 using content::WebContents;
+using extensions::Extension;
 
 class ExtensionInstallUIBrowserTest : public ExtensionBrowserTest {
  public:
   // Checks that a theme info bar is currently visible and issues an undo to
   // revert to the previous theme.
   void VerifyThemeInfoBarAndUndoInstall() {
     TabContentsWrapper* tab = browser()->GetSelectedTabContentsWrapper();
     ASSERT_TRUE(tab);
     InfoBarTabHelper* infobar_helper = tab->infobar_tab_helper();
     ASSERT_EQ(1U, infobar_helper->infobar_count());
@@ skipping 101 matching lines @@
   if (NewTabUI::ShouldShowApps()) {
     EXPECT_EQ(num_normal_tabs + 1, browser()->tab_count());
     WebContents* web_contents = browser()->GetSelectedWebContents();
     ASSERT_TRUE(web_contents);
     EXPECT_TRUE(StartsWithASCII(web_contents->GetURL().spec(),
                                 "chrome://newtab/", false));
   } else {
     // TODO(xiyuan): Figure out how to test extension installed bubble?
   }
 }