Fix hangs & crashes in teardown-during-Seek.

media/filters/ffmpeg_video_decoder.cc

 // 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.
 
 #include "media/filters/ffmpeg_video_decoder.h"
 
 #include <deque>
 
 #include "base/bind.h"
 #include "base/callback.h"
@@ skipping 237 matching lines @@
     pts_stream_.EnqueuePts(buffer.get());
   }
 
   // Otherwise, attempt to decode a single frame.
   decode_engine_->ConsumeVideoSample(buffer);
 }
 
 void FFmpegVideoDecoder::ProduceVideoFrame(
     scoped_refptr<VideoFrame> video_frame) {
   if (MessageLoop::current() != message_loop_) {
-    message_loop_->PostTask(FROM_HERE, base::Bind(
-        &FFmpegVideoDecoder::ProduceVideoFrame, this, video_frame));
+    if (state_ != kStopped) {
+      message_loop_->PostTask(FROM_HERE, base::Bind(
+          &FFmpegVideoDecoder::ProduceVideoFrame, this, video_frame));
+    }
     return;
   }
 
   DCHECK_EQ(MessageLoop::current(), message_loop_);
 
   // Synchronized flushing before stop should prevent this.
   DCHECK_NE(state_, kStopped);
 
   // If the decoding is finished, we just always return empty frames.
   if (state_ == kDecodeFinished) {
@@ skipping 65 matching lines @@
     decode_engine_->ProduceVideoFrame(video_frame);
   }
 }
 
 void FFmpegVideoDecoder::SetVideoDecodeEngineForTest(
     VideoDecodeEngine* engine) {
   decode_engine_.reset(engine);
 }
 
 }  // namespace media