Revert of Revert of Chromecast: Play audio streams not supported by CMA via default renderer

chromecast/media/base/switching_media_renderer.cc

Index: chromecast/media/base/switching_media_renderer.cc
diff --git a/chromecast/media/base/switching_media_renderer.cc b/chromecast/media/base/switching_media_renderer.cc
new file mode 100644
index 0000000000000000000000000000000000000000..16ffd12b77256b7d714f2766f654b0ca6f94c261
--- /dev/null
+++ b/chromecast/media/base/switching_media_renderer.cc
@@ -0,0 +1,102 @@
+// 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/base/switching_media_renderer.h"
+
+#include "base/logging.h"
+#include "media/base/audio_decoder_config.h"
+#include "media/base/demuxer_stream.h"
+#include "media/base/demuxer_stream_provider.h"
+
+namespace chromecast {
+namespace media {
+
+SwitchingMediaRenderer::SwitchingMediaRenderer(
+    scoped_ptr<::media::Renderer> default_renderer,
+    scoped_ptr<::media::Renderer> cma_renderer)
+    : default_renderer_(default_renderer.Pass()),
+    cma_renderer_(cma_renderer.Pass()) {
+      DCHECK(default_renderer_);
+      DCHECK(cma_renderer_);
+}
+
+SwitchingMediaRenderer::~SwitchingMediaRenderer() {
+}
+
+void SwitchingMediaRenderer::Initialize(
+    ::media::DemuxerStreamProvider* demuxer_stream_provider,
+    const base::Closure& init_cb,
+    const ::media::StatisticsCB& statistics_cb,
+    const ::media::BufferingStateCB& buffering_state_cb,
+    const ::media::Renderer::PaintCB& paint_cb,
+    const base::Closure& ended_cb,
+    const ::media::PipelineStatusCB& error_cb) {
+  // At this point the DemuxerStreamProvider should be fully initialized, so we
+  // have enough information to decide which renderer to use.
+  demuxer_stream_provider_ = demuxer_stream_provider;
+  DCHECK(demuxer_stream_provider_);
+  ::media::DemuxerStream* audio_stream =
+      demuxer_stream_provider_->GetStream(::media::DemuxerStream::AUDIO);
+  ::media::DemuxerStream* video_stream =
+      demuxer_stream_provider_->GetStream(::media::DemuxerStream::VIDEO);
+  if (audio_stream && !video_stream &&
+      audio_stream->audio_decoder_config().codec() != ::media::kCodecAAC &&
+      audio_stream->audio_decoder_config().codec() != ::media::kCodecVorbis) {
+    // We'll use the default Chrome media renderer with software audio decoding
+    cma_renderer_.reset();
+  } else {
+    // We'll use the CMA-based rendering with hardware decoding
+    default_renderer_.reset();
+  }
+
+  return GetRenderer()->Initialize(demuxer_stream_provider,
+                                   init_cb, statistics_cb, buffering_state_cb,
+                                   paint_cb, ended_cb, error_cb);
+}
+
+::media::Renderer* SwitchingMediaRenderer::GetRenderer() const {
+  DCHECK(default_renderer_ || cma_renderer_);
+  if (cma_renderer_)
+    return cma_renderer_.get();
+
+  DCHECK(default_renderer_);
+  return default_renderer_.get();
+}
+
+void SwitchingMediaRenderer::SetCdm(
+    ::media::CdmContext* cdm_context,
+    const ::media::CdmAttachedCB& cdm_attached_cb) {
+  GetRenderer()->SetCdm(cdm_context, cdm_attached_cb);
+}
+
+void SwitchingMediaRenderer::Flush(const base::Closure& flush_cb) {
+  GetRenderer()->Flush(flush_cb);
+}
+
+void SwitchingMediaRenderer::StartPlayingFrom(base::TimeDelta time) {
+  GetRenderer()->StartPlayingFrom(time);
+}
+
+void SwitchingMediaRenderer::SetPlaybackRate(float playback_rate)  {
+  GetRenderer()->SetPlaybackRate(playback_rate);
+}
+
+void SwitchingMediaRenderer::SetVolume(float volume)  {
+  GetRenderer()->SetVolume(volume);
+}
+
+base::TimeDelta SwitchingMediaRenderer::GetMediaTime()  {
+  return GetRenderer()->GetMediaTime();
+}
+
+bool SwitchingMediaRenderer::HasAudio() {
+  return GetRenderer()->HasAudio();
+}
+
+bool SwitchingMediaRenderer::HasVideo() {
+  return GetRenderer()->HasVideo();
+}
+
+}  // namespace media
+}  // namespace chromecast