Warn on missing OVERRIDE/virtual everywhere, not just in header files.

chrome/browser/extensions/extension_crash_recovery_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/process_util.h"
 #include "chrome/browser/browser_process.h"
 #include "chrome/browser/extensions/extension_browsertest.h"
 #include "chrome/browser/extensions/extension_host.h"
 #include "chrome/browser/extensions/extension_process_manager.h"
 #include "chrome/browser/extensions/extension_service.h"
@@ skipping 105 matching lines @@
   std::string second_extension_id_;
 
 };
 
 // TODO(rsesek): Implement and enable these tests. http://crbug.com/179904
 #if defined(ENABLE_MESSAGE_CENTER) && !defined(OS_MACOSX)
 
 class MessageCenterExtensionCrashRecoveryTest
     : public ExtensionCrashRecoveryTestBase {
  protected:
-  virtual void SetUpCommandLine(CommandLine* command_line) {
+  virtual void SetUpCommandLine(CommandLine* command_line) OVERRIDE {
     ExtensionCrashRecoveryTestBase::SetUpCommandLine(command_line);
     command_line->AppendSwitch(
         message_center::switches::kEnableRichNotifications);
   }
 
   virtual void AcceptNotification(size_t index) OVERRIDE {
     message_center::MessageCenter* message_center =
         message_center::MessageCenter::Get();
     ASSERT_GT(message_center->NotificationCount(), index);
     message_center::NotificationList::Notifications::reverse_iterator it =
@@ skipping 445 matching lines @@
                 GetController()));
     chrome::Reload(browser(), CURRENT_TAB);
     observer.Wait();
   }
   // Extension should now be loaded.
   SCOPED_TRACE("after reloading the tab");
   CheckExtensionConsistency(first_extension_id_);
   ASSERT_EQ(size_before + 1, GetExtensionService()->extensions()->size());
   ASSERT_EQ(0U, CountBalloons());
 }