Avoid deadlock between Pipeline and RendererImpl.

media/base/pipeline.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/base/pipeline.h"
 
 #include <algorithm>
 
 #include "base/bind.h"
 #include "base/callback.h"
@@ skipping 135 matching lines @@
   volume_ = volume;
   if (running_) {
     task_runner_->PostTask(
         FROM_HERE,
         base::Bind(
             &Pipeline::VolumeChangedTask, weak_factory_.GetWeakPtr(), volume));
   }
 }
 
 TimeDelta Pipeline::GetMediaTime() const {
+  if (!renderer_)
+    return TimeDelta();
+
+  TimeDelta media_time = renderer_->GetMediaTime();
+
   base::AutoLock auto_lock(lock_);
-  return renderer_ ? std::min(renderer_->GetMediaTime(), duration_)
-                   : TimeDelta();
+  return std::min(media_time, duration_);
 }
 
 Ranges<TimeDelta> Pipeline::GetBufferedTimeRanges() const {
   base::AutoLock auto_lock(lock_);
   return buffered_time_ranges_;
 }
 
 TimeDelta Pipeline::GetMediaDuration() const {
   base::AutoLock auto_lock(lock_);
   return duration_;
@@ skipping 263 matching lines @@
 }
 
 void Pipeline::OnStopCompleted(PipelineStatus status) {
   DVLOG(2) << __FUNCTION__;
   DCHECK(task_runner_->BelongsToCurrentThread());
   DCHECK_EQ(state_, kStopping);
   DCHECK(!renderer_);
   DCHECK(!text_renderer_);
 
   {
-    base::AutoLock l(lock_);
+    base::AutoLock auto_lock(lock_);
     running_ = false;
   }
 
   SetState(kStopped);
   filter_collection_.reset();
   demuxer_ = NULL;
 
   // If we stop during initialization/seeking we want to run |seek_cb_|
   // followed by |stop_cb_| so we don't leave outstanding callbacks around.
   if (!seek_cb_.is_null()) {
@@ skipping 216 matching lines @@
       base::Bind(&Pipeline::GetMediaDuration, base::Unretained(this)));
 }
 
 void Pipeline::BufferingStateChanged(BufferingState new_buffering_state) {
   DVLOG(1) << __FUNCTION__ << "(" << new_buffering_state << ") ";
   DCHECK(task_runner_->BelongsToCurrentThread());
   buffering_state_cb_.Run(new_buffering_state);
 }
 
 }  // namespace media