Decryptors can report kNoKey to WebMediaPlayer

media/filters/decrypting_audio_decoder.cc

Index: media/filters/decrypting_audio_decoder.cc
diff --git a/media/filters/decrypting_audio_decoder.cc b/media/filters/decrypting_audio_decoder.cc
index 0ca20f7a98b1ea19481c73060602bc4e7358162e..5e6f865b9e064929a6e800fa11574d7be74e9b0c 100644
--- a/media/filters/decrypting_audio_decoder.cc
+++ b/media/filters/decrypting_audio_decoder.cc
@@ -46,9 +46,11 @@ std::string DecryptingAudioDecoder::GetDisplayName() const {
   return "DecryptingAudioDecoder";
 }
 
-void DecryptingAudioDecoder::Initialize(const AudioDecoderConfig& config,
-                                        const PipelineStatusCB& status_cb,
-                                        const OutputCB& output_cb) {
+void DecryptingAudioDecoder::Initialize(
+    const AudioDecoderConfig& config,
+    const PipelineStatusCB& status_cb,
+    const OutputCB& output_cb,
+    const base::Closure& waiting_for_encryption_key_cb) {
   DVLOG(2) << "Initialize()";
   DCHECK(task_runner_->BelongsToCurrentThread());
   DCHECK(decode_cb_.is_null());
@@ -57,6 +59,7 @@ void DecryptingAudioDecoder::Initialize(const AudioDecoderConfig& config,
   weak_this_ = weak_factory_.GetWeakPtr();
   init_cb_ = BindToCurrentLoop(status_cb);
   output_cb_ = BindToCurrentLoop(output_cb);
+  waiting_for_encryption_key_cb_ = waiting_for_encryption_key_cb;
 
   if (!config.IsValidConfig()) {
     DLOG(ERROR) << "Invalid audio stream config.";
@@ -288,6 +291,7 @@ void DecryptingAudioDecoder::DeliverFrame(
     }
 
     state_ = kWaitingForKey;
+    waiting_for_encryption_key_cb_.Run();
     return;
   }