[4/4][Ozone-Drm] Keep track of DRM devices in browser process

ui/ozone/platform/drm/host/drm_device_handle.h

+// 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_HOST_DRM_DEVICE_HANDLE_H_
+#define UI_OZONE_PLATFORM_DRM_HOST_DRM_DEVICE_HANDLE_H_
+
+#include "base/files/file.h"
+
+namespace ui {
+
+class DrmDeviceHandle {
+ public:
+  DrmDeviceHandle();
+  ~DrmDeviceHandle();
+
+  bool Initialize(const base::FilePath& path);
+  void Shutdown();
+
+  bool IsValid() const;
+  base::File DuplicateFile();
+
+ private:
+  base::File file_;
+
+  DISALLOW_COPY_AND_ASSIGN(DrmDeviceHandle);
+};
+
+}  // namespace ui
+
+#endif  // UI_OZONE_PLATFORM_DRM_HOST_DRM_DEVICE_HANDLE_H_