[Chromecast] Allow CMA backend to notify of key expiry

chromecast/public/media/media_pipeline_backend.h

 // 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.
 
 #ifndef CHROMECAST_PUBLIC_MEDIA_MEDIA_PIPELINE_BACKEND_H_
 #define CHROMECAST_PUBLIC_MEDIA_MEDIA_PIPELINE_BACKEND_H_
 
+#include <stdint.h>
+#include <string>
+
+#include "cast_key_status.h"
 #include "decoder_config.h"
 
 namespace chromecast {
 struct Size;
 
 namespace media {
 class CastDecoderBuffer;
 class DecryptContext;
 
 // Interface for platform-specific output of media.
@@ skipping 117 matching lines @@
                                       BufferStatus status) = 0;
 
     // Must be called after an end-of-stream buffer has been rendered (ie, the
     // last real buffer has been sent to the output hardware).
     virtual void OnEndOfStream(Decoder* decoder) = 0;
 
     // May be called if a decoder error occurs. No more calls to PushBuffer()
     // will be made after this is called.
     virtual void OnDecoderError(Decoder* decoder) = 0;
 
+    // Must be called when a decryption key status changes.
+    virtual void OnKeyStatusChanged(const std::string& key_id,
+                                    CastKeyStatus key_status,
+                                    uint32_t system_code) = 0;
+
    protected:
     virtual ~Delegate() {}
   };
 
   virtual ~MediaPipelineBackend() {}
 
   // Creates a new AudioDecoder attached to this pipeline.  MediaPipelineBackend
   // maintains ownership of the decoder object (and must not delete before it's
   // destroyed).  Will be called zero or more times, all calls made before
   // Initialize. May return nullptr if the platform implementation cannot
@@ skipping 38 matching lines @@
   // Sets the playback rate.  |rate| > 0.  If this is not called, a default rate
   // of 1.0 is assumed. Returns true if successful. Only called when in
   // the "playing" or "paused" states.
   virtual bool SetPlaybackRate(float rate) = 0;
 };
 
 }  // namespace media
 }  // namespace chromecast
 
 #endif  // CHROMECAST_PUBLIC_MEDIA_MEDIA_PIPELINE_BACKEND_H_