Linux/ChromeOS Chromium style checker cleanup, chrome/browser/extensions edition.

chrome/browser/extensions/api/app/app_apitest.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/command_line.h"
 #include "chrome/browser/extensions/extension_apitest.h"
 #include "chrome/common/chrome_switches.h"
 
 class ExperimentalApiTest : public ExtensionApiTest {
  public:
-  void SetUpCommandLine(CommandLine* command_line) {
+  virtual void SetUpCommandLine(CommandLine* command_line) OVERRIDE {
     ExtensionApiTest::SetUpCommandLine(command_line);
     command_line->AppendSwitch(switches::kEnableExperimentalExtensionApis);
   }
 };
 
 IN_PROC_BROWSER_TEST_F(ExperimentalApiTest, AppNotificationIncognito) {
   ASSERT_TRUE(RunExtensionSubtest(
       "app_notifications", "test.html",
       ExtensionApiTest::kFlagEnableIncognito |
       ExtensionApiTest::kFlagUseIncognito)) << message_;
 }