gpu: Add GpuFence framework.

ui/gl/gl_fence_shared_event.h

+// Copyright 2016 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_GL_GL_FENCE_SHARED_EVENT_H_
+#define UI_GL_GL_FENCE_SHARED_EVENT_H_
+
+#include "base/macros.h"
+#include "ui/gfx/shared_event.h"
+#include "ui/gl/gl_export.h"
+#include "ui/gl/gl_fence.h"
+
+namespace gl {
+
+class GL_EXPORT GLFenceSharedEvent : public GLFence {
+ public:
+  explicit GLFenceSharedEvent(const gfx::SharedEventHandle& handle);
+  ~GLFenceSharedEvent() override;
+
+  // Overridden from GLFence:
+  bool HasCompleted() override;
+  void ClientWait() override;
+  void ServerWait() override;
+  bool SignalSupported() override;
+  void Signal() override;
+
+ private:
+  gfx::SharedEvent shared_event_;
+
+  DISALLOW_COPY_AND_ASSIGN(GLFenceSharedEvent);
+};
+
+}  // namespace gl
+
+#endif  // UI_GL_GL_FENCE_SHARED_EVENT_H_