Reland: Remove reference counting from media::VideoDecoder and friends.

media/filters/ffmpeg_video_decoder.cc

 // Copyright (c) 2012 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.
 
 #include "media/filters/ffmpeg_video_decoder.h"
 
 #include <algorithm>
 #include <string>
 
 #include "base/bind.h"
@@ skipping 40 matching lines @@
     return decode_threads;
 
   decode_threads = std::max(decode_threads, 0);
   decode_threads = std::min(decode_threads, kMaxDecodeThreads);
   return decode_threads;
 }
 
 FFmpegVideoDecoder::FFmpegVideoDecoder(
     const scoped_refptr<base::MessageLoopProxy>& message_loop)
     : message_loop_(message_loop),
+      weak_factory_(this),
       state_(kUninitialized),
       codec_context_(NULL),
       av_frame_(NULL) {
 }
 
 int FFmpegVideoDecoder::GetVideoBuffer(AVCodecContext* codec_context,
                                        AVFrame* frame) {
   // Don't use |codec_context_| here! With threaded decoding,
   // it will contain unsynchronized width/height/pix_fmt values,
   // whereas |codec_context| contains the current threads's
@@ skipping 56 matching lines @@
   // this callback
   memset(frame->data, 0, sizeof(frame->data));
   frame->opaque = NULL;
 }
 
 void FFmpegVideoDecoder::Initialize(const scoped_refptr<DemuxerStream>& stream,
                                     const PipelineStatusCB& status_cb,
                                     const StatisticsCB& statistics_cb) {
   DCHECK(message_loop_->BelongsToCurrentThread());
   PipelineStatusCB initialize_cb = BindToCurrentLoop(status_cb);
+  weak_this_ = weak_factory_.GetWeakPtr();
 
   FFmpegGlue::InitializeFFmpeg();
   DCHECK(!demuxer_stream_) << "Already initialized.";
 
   if (!stream) {
     initialize_cb.Run(PIPELINE_ERROR_DECODE);
     return;
   }
 
   demuxer_stream_ = stream;
@@ skipping 70 matching lines @@
   if (!decoded_frames_.empty()) {
     scoped_refptr<VideoFrame> frame = decoded_frames_.front();
     decoded_frames_.pop_front();
     base::ResetAndReturn(&read_cb_).Run(kOk, frame);
     return;
   }
 
   DCHECK_NE(state_, kUninitialized);
   DCHECK_NE(state_, kDecodeFinished);
   DCHECK(!read_cb_.is_null());
-  demuxer_stream_->Read(base::Bind(&FFmpegVideoDecoder::BufferReady, this));
+  demuxer_stream_->Read(base::Bind(
+      &FFmpegVideoDecoder::BufferReady, weak_this_));
 }
 
 void FFmpegVideoDecoder::BufferReady(
     DemuxerStream::Status status,
     const scoped_refptr<DecoderBuffer>& buffer) {
   DCHECK(message_loop_->BelongsToCurrentThread());
   DCHECK_NE(state_, kDecodeFinished);
   DCHECK_EQ(status != DemuxerStream::kOk, !buffer) << status;
 
   if (state_ == kUninitialized)
@@ skipping 235 matching lines @@
   if (!codec || avcodec_open2(codec_context_, codec, NULL) < 0) {
     ReleaseFFmpegResources();
     return false;
   }
 
   av_frame_ = avcodec_alloc_frame();
   return true;
 }
 
 }  // namespace media