Splits PipelineImpl into main and media thread components.

media/blink/webmediaplayer_impl.cc

 // Copyright 2013 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/blink/webmediaplayer_impl.h"
 
 #include <algorithm>
 #include <cmath>
 #include <limits>
 #include <string>
@@ skipping 212 matching lines @@
   // e.g. GetCurrentFrameFromCompositor(). See http://crbug.com/434861
 
   // Use the null sink if no sink was provided.
   audio_source_provider_ = new WebAudioSourceProviderImpl(
       params.audio_renderer_sink().get()
           ? params.audio_renderer_sink()
           : new NullAudioSink(media_task_runner_));
 }
 
 WebMediaPlayerImpl::~WebMediaPlayerImpl() {
-  client_->setWebLayer(NULL);
-
   DCHECK(main_task_runner_->BelongsToCurrentThread());
 
+  client_->setWebLayer(NULL);
   if (delegate_) {
     delegate_->PlayerGone(delegate_id_);
     delegate_->RemoveObserver(delegate_id_);
   }
 
-  // Abort any pending IO so stopping the pipeline doesn't get blocked.
   suppress_destruction_errors_ = true;

[sandersd (OOO until July 31), 2016/06/03 23:11:45]

Probably group this with setWebLayer().

[alokp, 2016/06/03 23:57:49]

Done.

-  if (data_source_)

[sandersd (OOO until July 31), 2016/06/03 23:11:45]

I don't see any change in PipelineImpl related to these deletions, but I'm also
not sure how Pipeline gets blocked. What's the reasoning here?

[alokp, 2016/06/03 23:57:49]

I can move these changes to a separate patch if you like. None of this code is
required. Pipeline::Stop stops the Demuxer, which in turn stops the data source
in correct order.

I also discovered that both - Demuxer and DataSource - have duplicate functions
named Stop, Abort, and Shutdown that do the same thing. We might be able to
remove some duplication there.

Pipeline::Stop blocks until the renderer is destroyed and demuxer is stopped on
the media thread using a WaitableEvent. We might be able to get rid of this
WaitableEvent if we moved the ownership of Demuxer and DataSource to
RendererWrapper. That would allow us to just post a DeleteSoon task for
RendererWrapper on the media thread. See my comment in Pipeline::Stop.

-    data_source_->Abort();
-  if (chunk_demuxer_) {
-    chunk_demuxer_->Shutdown();
-    chunk_demuxer_ = nullptr;
-  }
-
-  renderer_factory_.reset();
 
   // Pipeline must be stopped before it is destroyed.
   pipeline_.Stop();
 
   if (last_reported_memory_usage_)
     adjust_allocated_memory_cb_.Run(-last_reported_memory_usage_);
 
   compositor_task_runner_->DeleteSoon(FROM_HERE, compositor_);
 
   media_log_->AddEvent(
@@ skipping 1351 matching lines @@
            << ", Video: " << stats.video_memory_usage << ", DataSource: "
            << (data_source_ ? data_source_->GetMemoryUsage() : 0)
            << ", Demuxer: " << demuxer_memory_usage;
 
   const int64_t delta = current_memory_usage - last_reported_memory_usage_;
   last_reported_memory_usage_ = current_memory_usage;
   adjust_allocated_memory_cb_.Run(delta);
 }
 
 }  // namespace media