Decryptors can report kNoKey to WebMediaPlayer

media/base/audio_renderer.h

 // 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.
 
 #ifndef MEDIA_BASE_AUDIO_RENDERER_H_
 #define MEDIA_BASE_AUDIO_RENDERER_H_
 
 #include "base/callback.h"
 #include "base/time/time.h"
 #include "media/base/buffering_state.h"
@@ skipping 21 matching lines @@
   // |stream| is encrypted.
   //
   // |statistics_cb| is executed periodically with audio rendering stats.
   //
   // |buffering_state_cb| is executed when audio rendering has either run out of
   // data or has enough data to continue playback.
   //
   // |ended_cb| is executed when audio rendering has reached the end of stream.
   //
   // |error_cb| is executed if an error was encountered after initialization.
-  virtual void Initialize(DemuxerStream* stream,
-                          const PipelineStatusCB& init_cb,
-                          const SetDecryptorReadyCB& set_decryptor_ready_cb,
-                          const StatisticsCB& statistics_cb,
-                          const BufferingStateCB& buffering_state_cb,
-                          const base::Closure& ended_cb,
-                          const PipelineStatusCB& error_cb) = 0;
+  //
+  // |waiting_for_decryption_key_cb| is called whenever the key needed to
+  // decrypt the stream is not available.
+  virtual void Initialize(
+      DemuxerStream* stream,
+      const PipelineStatusCB& init_cb,
+      const SetDecryptorReadyCB& set_decryptor_ready_cb,
+      const StatisticsCB& statistics_cb,
+      const BufferingStateCB& buffering_state_cb,
+      const base::Closure& ended_cb,
+      const PipelineStatusCB& error_cb,
+      const base::Closure& waiting_for_decryption_key_cb) = 0;
 
   // Returns the TimeSource associated with audio rendering.
   virtual TimeSource* GetTimeSource() = 0;
 
   // Discard any audio data, executing |callback| when completed.
   //
   // Clients should expect |buffering_state_cb| to be called with
   // BUFFERING_HAVE_NOTHING while flushing is in progress.
   virtual void Flush(const base::Closure& callback) = 0;
 
   // Starts playback by reading from |stream| and decoding and rendering audio.
   //
   // Only valid to call after a successful Initialize() or Flush().
   virtual void StartPlaying() = 0;
 
   // Sets the output volume.
   virtual void SetVolume(float volume) = 0;
 
  private:
   DISALLOW_COPY_AND_ASSIGN(AudioRenderer);
 };
 
 }  // namespace media
 
 #endif  // MEDIA_BASE_AUDIO_RENDERER_H_