Simple Jitter Test for AudioConverter.

media/audio/fake_audio_consumer.cc

 // Copyright (c) 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/audio/fake_audio_consumer.h"
 
 #include "base/bind.h"
 #include "base/bind_helpers.h"
 #include "base/logging.h"
 #include "base/message_loop.h"
@@ skipping 32 matching lines @@
   DCHECK(message_loop_->BelongsToCurrentThread());
   read_cb_.Reset();
   read_task_cb_.Cancel();
 }
 
 void FakeAudioConsumer::DoRead() {
   DCHECK(message_loop_->BelongsToCurrentThread());
   DCHECK(!read_cb_.is_null());
 
   read_cb_.Run(audio_bus_.get());
+  if (read_cb_.is_null())
+    return;
 
   // Need to account for time spent here due to the cost of |read_cb_| as well
   // as the imprecision of PostDelayedTask().
   base::Time now = base::Time::Now();
   base::TimeDelta delay = next_read_time_ + buffer_duration_ - now;
 
   // If we're behind, find the next nearest ontime interval.
   if (delay < base::TimeDelta())
     delay += buffer_duration_ * (-delay / buffer_duration_ + 1);
   next_read_time_ = now + delay;
 
   message_loop_->PostDelayedTask(FROM_HERE, read_task_cb_.callback(), delay);
 }
 
 }  // namespace media