Enable Clang warnings in .cc files for Linux+[Aura/ChromeOS]

chrome/browser/chromeos/system/ash_system_tray_delegate.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 "chrome/browser/chromeos/system/ash_system_tray_delegate.h"
 
 #include <algorithm>
 #include <set>
 #include <string>
 #include <vector>
@@ skipping 1384 matching lines @@
       input_method::InputMethodManager* manager, bool show_message) OVERRIDE {
     GetSystemTrayNotifier()->NotifyRefreshIME(show_message);
   }
 
   virtual void InputMethodPropertyChanged(
       input_method::InputMethodManager* manager) OVERRIDE {
     GetSystemTrayNotifier()->NotifyRefreshIME(false);
   }
 
   // drive::JobListObserver overrides.
-  virtual void OnJobAdded(const drive::JobInfo& job_info) {
+  virtual void OnJobAdded(const drive::JobInfo& job_info) OVERRIDE {
     OnJobUpdated(job_info);
   }
 
   virtual void OnJobDone(const drive::JobInfo& job_info,
-                         drive::FileError error) {
+                         drive::FileError error) OVERRIDE {
     ash::DriveOperationStatus status;
     if (ConvertToFinishedDriveOperationStatus(job_info, error, &status))
       GetSystemTrayNotifier()->NotifyDriveJobUpdated(status);
   }
 
-  virtual void OnJobUpdated(const drive::JobInfo& job_info) {
+  virtual void OnJobUpdated(const drive::JobInfo& job_info) OVERRIDE {
     ash::DriveOperationStatus status;
     if (ConvertToDriveOperationStatus(job_info, &status))
       GetSystemTrayNotifier()->NotifyDriveJobUpdated(status);
   }
 
   DriveSystemService* FindDriveSystemService() {
     Profile* profile = ProfileManager::GetDefaultProfile();
     return DriveSystemServiceFactory::FindForProfile(profile);
   }
 
@@ skipping 191 matching lines @@
   DISALLOW_COPY_AND_ASSIGN(SystemTrayDelegate);
 };
 
 }  // namespace
 
 ash::SystemTrayDelegate* CreateSystemTrayDelegate() {
   return new chromeos::SystemTrayDelegate();
 }
 
 }  // namespace chromeos