Pick up starting position from OpenSLES getPosition().

media/audio/android/opensles_output.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/audio/android/opensles_output.h"
 
 #include "base/logging.h"
 #include "base/macros.h"
 #include "base/trace_event/trace_event.h"
 #include "media/audio/android/audio_manager_android.h"
@@ skipping 69 matching lines @@
   DCHECK(thread_checker_.CalledOnValidThread());
   DCHECK(callback);
   DCHECK(player_);
   DCHECK(simple_buffer_queue_);
   if (started_)
     return;
 
   base::AutoLock lock(lock_);
   DCHECK(!callback_);
   callback_ = callback;
-  delay_calculator_.SetBaseTimestamp(base::TimeDelta());
 
   // Fill audio data with silence to avoid start-up glitches. Don't use
   // FillBufferQueueNoLock() since it can trigger recursive entry if an error
   // occurs while writing into the stream. See http://crbug.com/624877.
   memset(audio_data_[active_buffer_index_], 0, buffer_size_bytes_);
-  delay_calculator_.AddFrames(audio_bus_->frames());
   LOG_ON_FAILURE_AND_RETURN((*simple_buffer_queue_)
                                 ->Enqueue(simple_buffer_queue_,
                                           audio_data_[active_buffer_index_],
                                           buffer_size_bytes_));
   active_buffer_index_ = (active_buffer_index_ + 1) % kMaxNumOfBuffersInQueue;
 
   // Start streaming data by setting the play state to SL_PLAYSTATE_PLAYING.
   // For a player object, when the object is in the SL_PLAYSTATE_PLAYING
   // state, adding buffers will implicitly start playback.
   LOG_ON_FAILURE_AND_RETURN(
       (*player_)->SetPlayState(player_, SL_PLAYSTATE_PLAYING));
 
+  // On older version of Android, the position may not be reset even though we
+  // call Clear() during Stop(), in this case the best we can do is assume that
+  // we're continuing on from this previous position.
+  uint32_t position_in_ms = 0;
+  LOG_ON_FAILURE_AND_RETURN((*player_)->GetPosition(player_, &position_in_ms));
+  delay_calculator_.SetBaseTimestamp(
+      base::TimeDelta::FromMilliseconds(position_in_ms));
+  delay_calculator_.AddFrames(audio_bus_->frames());
+
   started_ = true;
 }
 
 void OpenSLESOutputStream::Stop() {
   DVLOG(2) << "OpenSLESOutputStream::Stop()";
   DCHECK(thread_checker_.CalledOnValidThread());
   if (!started_)
     return;
 
   base::AutoLock lock(lock_);
@@ skipping 268 matching lines @@
   }
 }
 
 void OpenSLESOutputStream::HandleError(SLresult error) {
   DLOG(ERROR) << "OpenSLES Output error " << error;
   if (callback_)
     callback_->OnError(this);
 }
 
 }  // namespace media