Fix compile error with clang and use_aura=1

apps/shell/browser/shell_desktop_controller.cc

 // Copyright 2014 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 "apps/shell/browser/shell_desktop_controller.h"
 
 #include "third_party/skia/include/core/SkColor.h"
 #include "ui/aura/env.h"
 #include "ui/aura/test/test_screen.h"
 #include "ui/aura/window_event_dispatcher.h"
@@ skipping 57 matching lines @@
   DestroyRootWindow();
   aura::Env::DeleteInstance();
 }
 
 aura::WindowTreeHost* ShellDesktopController::GetWindowTreeHost() {
   return wm_test_helper_->host();
 }
 
 #if defined(OS_CHROMEOS) && defined(USE_X11)
 void ShellDesktopController::OnDisplayModeChanged(
-    const std::vector<ui::OutputConfigurator::DisplayState>& outputs) OVERRIDE {
+    const std::vector<ui::OutputConfigurator::DisplayState>& outputs) {
   gfx::Size size = GetPrimaryDisplaySize();
   if (!size.IsEmpty())
     wm_test_helper_->host()->UpdateRootWindowSize(size);
 }
 #endif
 
 void ShellDesktopController::CreateRootWindow() {
   test_screen_.reset(aura::TestScreen::Create());
   // TODO(jamescook): Replace this with a real Screen implementation.
   gfx::Screen::SetScreenInstance(gfx::SCREEN_TYPE_NATIVE, test_screen_.get());
@@ skipping 23 matching lines @@
   if (states.empty())
     return gfx::Size();
   const ui::DisplayMode* mode = states[0].display->current_mode();
   return mode ? mode->size() : gfx::Size();
 #else
   return gfx::Size();
 #endif
 }
 
 }  // namespace apps