Collapse FFmpegVideoDecodeEngine into FFmpegVideoDecoder and remove VideoDecodeEngine.

media/video/video_decode_engine.h

-// Copyright (c) 2011 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 MEDIA_VIDEO_VIDEO_DECODE_ENGINE_H_
-#define MEDIA_VIDEO_VIDEO_DECODE_ENGINE_H_
-
-#include "base/memory/ref_counted.h"
-#include "media/base/media_export.h"
-
-namespace media {
-
-class Buffer;
-class VideoDecoderConfig;
-class VideoFrame;
-
-class MEDIA_EXPORT VideoDecodeEngine {
- public:
-  virtual ~VideoDecodeEngine() {}
-
-  // Initialize the engine with specified configuration, returning true if
-  // successful.
-  virtual bool Initialize(const VideoDecoderConfig& config) = 0;
-
-  // Uninitialize the engine, freeing all resources. Calls to Flush() or
-  // Decode() will have no effect afterwards.
-  virtual void Uninitialize() = 0;
-
-  // Decode the encoded video data and store the result (if any) into
-  // |video_frame|. Note that a frame may not always be produced if the
-  // decode engine has insufficient encoded data. In such circumstances,
-  // additional calls to Decode() may be required.
-  //
-  // Returns true if decoding was successful (includes zero length input and end
-  // of stream), false if a decoding error occurred.
-  virtual bool Decode(const scoped_refptr<Buffer>& buffer,
-                      scoped_refptr<VideoFrame>* video_frame) = 0;
-
-  // Discard all pending data that has yet to be returned via Decode().
-  virtual void Flush() = 0;
-};
-
-}  // namespace media
-
-#endif  // MEDIA_VIDEO_VIDEO_DECODE_ENGINE_H_