MSE: Replace crossfade splicing overlap trimming.

media/renderers/audio_renderer_impl.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/renderers/audio_renderer_impl.h"
 
 #include <math.h>
 #include <stddef.h>
 #include <algorithm>
 #include <utility>
@@ skipping 768 matching lines @@
       return 0;
     }
 
     // Mute audio by returning 0 when not playing.
     if (state_ != kPlaying) {
       audio_clock_->WroteAudio(0, frames_requested, frames_delayed,
                                playback_rate_);
       return 0;
     }
 
-    // Delay playback by writing silence if we haven't reached the first
-    // timestamp yet; this can occur if the video starts before the audio.
     if (algorithm_->frames_buffered() > 0) {
-      CHECK_NE(first_packet_timestamp_, kNoTimestamp);
       CHECK_GE(first_packet_timestamp_, base::TimeDelta());
+
+      // Delay playback by writing silence if we haven't reached the first
+      // timestamp yet; this can occur if the video starts before the audio.
       const base::TimeDelta play_delay =
           first_packet_timestamp_ - audio_clock_->back_timestamp();
       if (play_delay > base::TimeDelta()) {
         DCHECK_EQ(frames_written, 0);
 
         // Don't multiply |play_delay| out since it can be a huge value on
         // poorly encoded media and multiplying by the sample rate could cause
         // the value to overflow.
         if (play_delay.InSecondsF() > static_cast<double>(frames_requested) /
                                           audio_parameters_.sample_rate()) {
@@ skipping 143 matching lines @@
   DCHECK_NE(buffering_state_, buffering_state);
   lock_.AssertAcquired();
   buffering_state_ = buffering_state;
 
   task_runner_->PostTask(
       FROM_HERE, base::Bind(&AudioRendererImpl::OnBufferingStateChange,
                             weak_factory_.GetWeakPtr(), buffering_state_));
 }
 
 }  // namespace media