ozone: Add post message loop initialization hook

ui/ozone/platform/caca/ozone_platform_caca.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 "ui/ozone/platform/caca/ozone_platform_caca.h"
 
 #include "ui/events/ozone/layout/keyboard_layout_engine_manager.h"
 #include "ui/events/ozone/layout/no/no_keyboard_layout_engine.h"
 #include "ui/ozone/common/native_display_delegate_ozone.h"
 #include "ui/ozone/platform/caca/caca_event_source.h"
@@ skipping 54 matching lines @@
     gpu_platform_support_host_.reset(CreateStubGpuPlatformSupportHost());
     input_controller_ = CreateStubInputController();
     KeyboardLayoutEngineManager::SetKeyboardLayoutEngine(
         make_scoped_ptr(new NoKeyboardLayoutEngine()));
   }
 
   void InitializeGPU() override {
     gpu_platform_support_.reset(CreateStubGpuPlatformSupport());
   }
 
+  void InitializeGpuPostMainLoop() override {}
+
  private:
   scoped_ptr<CacaWindowManager> window_manager_;
   scoped_ptr<CacaEventSource> event_source_;
   scoped_ptr<CursorFactoryOzone> cursor_factory_ozone_;
   scoped_ptr<GpuPlatformSupport> gpu_platform_support_;
   scoped_ptr<GpuPlatformSupportHost> gpu_platform_support_host_;
   scoped_ptr<InputController> input_controller_;
 
   DISALLOW_COPY_AND_ASSIGN(OzonePlatformCaca);
 };
 
 }  // namespace
 
 OzonePlatform* CreateOzonePlatformCaca() {
   return new OzonePlatformCaca;
 }
 
 }  // namespace ui