Switch DRM platform to using a separate thread

ui/ozone/platform/drm/gpu/drm_thread_proxy.h

Index: ui/ozone/platform/drm/gpu/drm_thread_proxy.h
diff --git a/ui/ozone/platform/drm/gpu/drm_thread_proxy.h b/ui/ozone/platform/drm/gpu/drm_thread_proxy.h
new file mode 100644
index 0000000000000000000000000000000000000000..fdad1b07fa630e63107d7ce503a1541382604397
--- /dev/null
+++ b/ui/ozone/platform/drm/gpu/drm_thread_proxy.h
@@ -0,0 +1,43 @@
+// Copyright 2015 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.
+
+#ifndef UI_OZONE_PLATFORM_DRM_GPU_DRM_THREAD_PROXY_H_
+#define UI_OZONE_PLATFORM_DRM_GPU_DRM_THREAD_PROXY_H_
+
+#include "base/memory/ref_counted.h"
+#include "base/memory/scoped_ptr.h"
+#include "ui/ozone/platform/drm/gpu/drm_thread.h"
+
+namespace ui {
+
+class DrmThreadMessageProxy;
+class DrmWindowProxy;
+
+// Mediates the communication between GPU main/IO threads and the DRM thread. It
+// serves proxy objects that are safe to call on the GPU threads. The proxy
+// objects then deal with safely posting the messages to the DRM thread.
+class DrmThreadProxy {
+ public:
+  explicit DrmThreadProxy();
+  ~DrmThreadProxy();
+
+  scoped_refptr<DrmThreadMessageProxy> CreateDrmThreadMessageProxy();
+
+  scoped_ptr<DrmWindowProxy> CreateDrmWindowProxy(
+      gfx::AcceleratedWidget widget);
+
+  scoped_refptr<GbmBuffer> CreateBuffer(gfx::AcceleratedWidget widget,
+                                        const gfx::Size& size,
+                                        gfx::BufferFormat format,
+                                        gfx::BufferUsage usage);
+
+ private:
+  DrmThread drm_thread_;
+
+  DISALLOW_COPY_AND_ASSIGN(DrmThreadProxy);
+};
+
+}  // namespace ui
+
+#endif  // UI_OZONE_PLATFORM_DRM_GPU_DRM_THREAD_PROXY_H_