MediaSourceDelegate: Fix DecryptingDemuxerStream initialization logic.

content/renderer/media/android/media_source_delegate.cc

 // Copyright 2013 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 "content/renderer/media/android/media_source_delegate.h"
 
 #include <limits>
 #include <string>
 #include <utility>
 #include <vector>
@@ skipping 135 matching lines @@
 void MediaSourceDelegate::InitializeMediaSource(
     const MediaSourceOpenedCB& media_source_opened_cb,
     const media::Demuxer::EncryptedMediaInitDataCB&
         encrypted_media_init_data_cb,
     const media::SetCdmReadyCB& set_cdm_ready_cb,
     const UpdateNetworkStateCB& update_network_state_cb,
     const DurationChangeCB& duration_change_cb,
     const base::Closure& waiting_for_decryption_key_cb) {
   DCHECK(main_task_runner_->BelongsToCurrentThread());
   DCHECK(!media_source_opened_cb.is_null());
+  DCHECK(!encrypted_media_init_data_cb.is_null());
+  DCHECK(!update_network_state_cb.is_null());
+  DCHECK(!duration_change_cb.is_null());
+  DCHECK(!waiting_for_decryption_key_cb.is_null());
+  DCHECK(!set_cdm_ready_cb.is_null());

[ddorwin, 2016/01/29 18:16:28]

nit: This one is out of order.

[xhwang, 2016/02/01 23:35:25]

Done.

+
   media_source_opened_cb_ = media_source_opened_cb;
   encrypted_media_init_data_cb_ = encrypted_media_init_data_cb;
   set_cdm_ready_cb_ = media::BindToCurrentLoop(set_cdm_ready_cb);
   update_network_state_cb_ = media::BindToCurrentLoop(update_network_state_cb);
   duration_change_cb_ = duration_change_cb;
   waiting_for_decryption_key_cb_ =
       media::BindToCurrentLoop(waiting_for_decryption_key_cb);
   access_unit_size_ = kAccessUnitSizeForMediaSource;
 
   chunk_demuxer_.reset(new media::ChunkDemuxer(
@@ skipping 323 matching lines @@
   DCHECK(chunk_demuxer_);
 
   if (status != media::PIPELINE_OK) {
     OnDemuxerError(status);
     return;
   }
 
   audio_stream_ = chunk_demuxer_->GetStream(DemuxerStream::AUDIO);
   video_stream_ = chunk_demuxer_->GetStream(DemuxerStream::VIDEO);
 
-  if (audio_stream_ && audio_stream_->audio_decoder_config().is_encrypted() &&
-      !set_cdm_ready_cb_.is_null()) {
+  if (audio_stream_ && audio_stream_->audio_decoder_config().is_encrypted()) {
     InitAudioDecryptingDemuxerStream();
     // InitVideoDecryptingDemuxerStream() will be called in
     // OnAudioDecryptingDemuxerStreamInitDone().
     return;
   }
 
-  if (video_stream_ && video_stream_->video_decoder_config().is_encrypted() &&
-      !set_cdm_ready_cb_.is_null()) {
+  if (video_stream_ && video_stream_->video_decoder_config().is_encrypted()) {
     InitVideoDecryptingDemuxerStream();
     return;
   }
 
   // Notify demuxer ready when both streams are not encrypted.
   is_demuxer_ready_ = true;
   NotifyDemuxerReady();
 }
 
 void MediaSourceDelegate::InitAudioDecryptingDemuxerStream() {
   DCHECK(media_task_runner_->BelongsToCurrentThread());
   DVLOG(1) << __FUNCTION__ << " : " << demuxer_client_id_;
   DCHECK(!set_cdm_ready_cb_.is_null());
-
   audio_decrypting_demuxer_stream_.reset(new media::DecryptingDemuxerStream(
       media_task_runner_, media_log_, waiting_for_decryption_key_cb_));
   audio_decrypting_demuxer_stream_->Initialize(
       audio_stream_, set_cdm_ready_cb_,
       base::Bind(&MediaSourceDelegate::OnAudioDecryptingDemuxerStreamInitDone,
                  media_weak_factory_.GetWeakPtr()));
 }
 
 void MediaSourceDelegate::InitVideoDecryptingDemuxerStream() {
   DCHECK(media_task_runner_->BelongsToCurrentThread());
   DVLOG(1) << __FUNCTION__ << " : " << demuxer_client_id_;
   DCHECK(!set_cdm_ready_cb_.is_null());
 
   video_decrypting_demuxer_stream_.reset(new media::DecryptingDemuxerStream(
       media_task_runner_, media_log_, waiting_for_decryption_key_cb_));
   video_decrypting_demuxer_stream_->Initialize(
       video_stream_, set_cdm_ready_cb_,
       base::Bind(&MediaSourceDelegate::OnVideoDecryptingDemuxerStreamInitDone,
                  media_weak_factory_.GetWeakPtr()));
 }
 
 void MediaSourceDelegate::OnAudioDecryptingDemuxerStreamInitDone(
     media::PipelineStatus status) {
   DCHECK(media_task_runner_->BelongsToCurrentThread());
   DVLOG(1) << __FUNCTION__ << "(" << status << ") : " << demuxer_client_id_;
   DCHECK(chunk_demuxer_);
 
-  if (status != media::PIPELINE_OK)
+  if (status != media::PIPELINE_OK) {
     audio_decrypting_demuxer_stream_.reset();
-  else
-    audio_stream_ = audio_decrypting_demuxer_stream_.get();
+    // DecryptingDemuxerStream cannot be used to decrypt the audio stream (e.g.
+    // the CDM doesn't support decrypt-only). It's still possible that we can
+    // decrypt and decode audio in the browser. Declare demuxer ready now to try
+    // that path.
+    // Note there's no need to try DecryptingDemuxerStream for video here since
+    // it is impossible to decrypt and decode audio in the browser and do

[ddorwin, 2016/01/29 18:16:28]

Thanks - this is helpful.
I believe the fundamental reason (regardless of an implementation limitations)
because this would involve using different CDMs. You might be explicit about
that here and in the description.

[xhwang, 2016/02/01 23:35:25]

Done.

+    // decrypt-only in the render process.
+    is_demuxer_ready_ = true;
+    NotifyDemuxerReady();
+    return;
+  }
+
+  audio_stream_ = audio_decrypting_demuxer_stream_.get();
 
   if (video_stream_ && video_stream_->video_decoder_config().is_encrypted()) {
     InitVideoDecryptingDemuxerStream();
     return;
   }
 
   // Try to notify demuxer ready when audio DDS initialization finished and
   // video is not encrypted.
   is_demuxer_ready_ = true;
   NotifyDemuxerReady();
@@ skipping 186 matching lines @@
     configs->video_codec = config.codec();
     configs->video_size = config.natural_size();
     configs->is_video_encrypted = config.is_encrypted();
     configs->video_extra_data = config.extra_data();
     return true;
   }
   return false;
 }
 
 }  // namespace content