[Chromecast] Fade in after a mixer input stream has skipped

chromecast/media/cma/backend/alsa/stream_mixer_alsa_input_impl.cc

 // Copyright 2015 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 "chromecast/media/cma/backend/alsa/stream_mixer_alsa_input_impl.h"
 
 #include <algorithm>
 #include <limits>
 
 #include "base/bind.h"
@@ skipping 217 matching lines @@
   DCHECK(!IsDeleting());
   if (end_of_stream) {
     LOG(INFO) << "End of stream for " << this;
     state_ = kStateGotEos;
   } else if (state_ == kStateUninitialized) {
     state_ = kStateNormalPlayback;
   }
   mixer_->OnFramesQueued();
 }
 
+void StreamMixerAlsaInputImpl::OnSkipped() {
+  DCHECK(mixer_task_runner_->BelongsToCurrentThread());
+  if (state_ == kStateNormalPlayback) {
+    // Fade in once this input starts providing data again.
+    fade_frames_remaining_ = NormalFadeFrames();
+  }
+}
+
 void StreamMixerAlsaInputImpl::AfterWriteFrames(
     const MediaPipelineBackendAlsa::RenderingDelay& mixer_rendering_delay) {
   DCHECK(mixer_task_runner_->BelongsToCurrentThread());
   double resampler_queued_frames =
       (resampler_ ? resampler_->BufferedFrames() : 0);
 
   bool queued_more_data = false;
   MediaPipelineBackendAlsa::RenderingDelay total_delay;
   {
     base::AutoLock lock(queue_lock_);
@@ skipping 253 matching lines @@
   DCHECK(!IsDeleting());
   if (multiplier > 1.0f)
     multiplier = 1.0f;
   if (multiplier < 0.0f)
     multiplier = 0.0f;
   volume_multiplier_ = multiplier;
 }
 
 }  // namespace media
 }  // namespace chromecast