[Mojo Video Capture] Move SharedMem Tracker/BufferHandle/Factory from content to media

content/browser/renderer_host/media/shared_memory_buffer_handle.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 CONTENT_BROWSER_RENDERER_HOST_MEDIA_SHARED_MEMORY_BUFFER_HANDLE_H_
-#define CONTENT_BROWSER_RENDERER_HOST_MEDIA_SHARED_MEMORY_BUFFER_HANDLE_H_
-
-#include "media/capture/video/video_capture_buffer_handle.h"
-
-namespace content {
-
-class SharedMemoryBufferTracker;
-
-// A simple proxy that implements the BufferHandle interface, providing
-// accessors to SharedMemTracker's memory and properties.
-class SharedMemoryBufferHandle : public media::VideoCaptureBufferHandle {
- public:
-  // |tracker| must outlive SimpleBufferHandle. This is ensured since a
-  // tracker is pinned until ownership of this SimpleBufferHandle is returned
-  // to VideoCaptureBufferPool.
-  explicit SharedMemoryBufferHandle(SharedMemoryBufferTracker* tracker);
-  ~SharedMemoryBufferHandle() override;
-
-  gfx::Size dimensions() const override;
-  size_t mapped_size() const override;
-  void* data(int plane) override;
-#if defined(OS_POSIX) && !defined(OS_MACOSX)
-  base::FileDescriptor AsPlatformFile() override;
-#endif
-  bool IsBackedByVideoFrame() const override;
-  scoped_refptr<media::VideoFrame> GetVideoFrame() override;
-
- private:
-  SharedMemoryBufferTracker* const tracker_;
-};
-
-}  // namespace content
-
-#endif  // CONTENT_BROWSER_RENDERER_HOST_MEDIA_SHARED_MEMORY_BUFFER_HANDLE_H_