media: Remove SetCdmReadyCB and CdmReadyCB (part 1).

media/base/audio_renderer.h

Index: media/base/audio_renderer.h
diff --git a/media/base/audio_renderer.h b/media/base/audio_renderer.h
index 79438c785bfb0e6634f9b892cdd4029918b8f328..11e112f1a1e97d8889b4e0366be1ccc8302a2b83 100644
--- a/media/base/audio_renderer.h
+++ b/media/base/audio_renderer.h
@@ -9,12 +9,12 @@
 #include "base/macros.h"
 #include "base/time/time.h"
 #include "media/base/buffering_state.h"
-#include "media/base/cdm_context.h"
 #include "media/base/media_export.h"
 #include "media/base/pipeline_status.h"
 
 namespace media {
 
+class CdmContext;
 class DemuxerStream;
 class TimeSource;
 
@@ -29,8 +29,8 @@ class MEDIA_EXPORT AudioRenderer {
   // completion. If initialization fails, only |init_cb| (not |error_cb|) will
   // be called.
   //
-  // |set_cdm_ready_cb| is fired when a CDM is needed, i.e. when the |stream| is
-  // encrypted.
+  // |cdm_context| can be used to handle encrypted streams. May be null if the
+  // stream is not encrypted.
   //
   // |statistics_cb| is executed periodically with audio rendering stats.
   //
@@ -46,7 +46,7 @@ class MEDIA_EXPORT AudioRenderer {
   virtual void Initialize(
       DemuxerStream* stream,
       const PipelineStatusCB& init_cb,
-      const SetCdmReadyCB& set_cdm_ready_cb,
+      CdmContext* cdm_context,
       const StatisticsCB& statistics_cb,
       const BufferingStateCB& buffering_state_cb,
       const base::Closure& ended_cb,