Wire up cursor proxy on MUS

ui/ozone/platform/drm/ozone_platform_gbm.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/drm/ozone_platform_gbm.h"
 
 #include <dlfcn.h>
 #include <fcntl.h>
 #include <gbm.h>
 #include <stdlib.h>
@@ skipping 131 matching lines @@
 #endif
     event_factory_ozone_.reset(new EventFactoryEvdev(
         cursor_.get(), device_manager_.get(),
         KeyboardLayoutEngineManager::GetKeyboardLayoutEngine()));
 
     GpuThreadAdapter* adapter;
     if (RunningInsideMus()) {
       gl_api_loader_.reset(new GlApiLoader());
       mus_thread_proxy_.reset(new MusThreadProxy());
       adapter = mus_thread_proxy_.get();
+      cursor_->SetDrmCursorProxy(mus_thread_proxy_.get());
     } else {
       gpu_platform_support_host_.reset(
           new DrmGpuPlatformSupportHost(cursor_.get()));
       adapter = gpu_platform_support_host_.get();
     }
 
     display_manager_.reset(
         new DrmDisplayHostManager(adapter, device_manager_.get(),
                                   event_factory_ozone_->input_controller()));
     cursor_factory_ozone_.reset(new BitmapCursorFactoryOzone);
@@ skipping 57 matching lines @@
   DISALLOW_COPY_AND_ASSIGN(OzonePlatformGbm);
 };
 
 }  // namespace
 
 OzonePlatform* CreateOzonePlatformGbm() {
   return new OzonePlatformGbm;
 }
 
 }  // namespace ui