Revert 290359 "Remove AudioBuffersState class."

trunk/src/media/audio/win/audio_low_latency_output_win.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/win/audio_low_latency_output_win.h"
 
 #include <Functiondiscoverykeys_devpkey.h>
 
 #include "base/command_line.h"
 #include "base/debug/trace_event.h"
@@ skipping 480 matching lines @@
           num_written_frames_ + packet_size_frames_;
 
       // Derive the actual delay value which will be fed to the
       // render client using the OnMoreData() callback.
       audio_delay_bytes = (pos_last_sample_written_frames -
           pos_sample_playing_frames) *  format_.Format.nBlockAlign;
     }
 
     // Read a data packet from the registered client source and
     // deliver a delay estimate in the same callback to the client.
+    // A time stamp is also stored in the AudioBuffersState. This
+    // time stamp can be used at the client side to compensate for
+    // the delay between the usage of the delay value and the time
+    // of generation.
 
     int frames_filled = source_->OnMoreData(
-        audio_bus_.get(), audio_delay_bytes);
+        audio_bus_.get(), AudioBuffersState(0, audio_delay_bytes));
     uint32 num_filled_bytes = frames_filled * format_.Format.nBlockAlign;
     DCHECK_LE(num_filled_bytes, packet_size_bytes_);
 
     // Note: If this ever changes to output raw float the data must be
     // clipped and sanitized since it may come from an untrusted
     // source such as NaCl.
     const int bytes_per_sample = format_.Format.wBitsPerSample >> 3;
     audio_bus_->Scale(volume_);
     audio_bus_->ToInterleaved(
         frames_filled, bytes_per_sample, audio_data);
@@ skipping 102 matching lines @@
 
     // Ensure that we don't quit the main thread loop immediately next
     // time Start() is called.
     ResetEvent(stop_render_event_.Get());
   }
 
   source_ = NULL;
 }
 
 }  // namespace media