media: Always provide CdmContext when selecting decoder in DecoderStream

media/filters/decoder_stream.h

Index: media/filters/decoder_stream.h
diff --git a/media/filters/decoder_stream.h b/media/filters/decoder_stream.h
index 2a7d8497c2bbb030fa0ca6e122c9e13839d41e65..cf9dcd91ae756983d1d2c030222a3c7fc7028dcd 100644
--- a/media/filters/decoder_stream.h
+++ b/media/filters/decoder_stream.h
@@ -136,7 +136,7 @@ class MEDIA_EXPORT DecoderStream {
     STATE_ERROR,
   };
 
-  void SelectDecoder(CdmContext* cdm_context);
+  void SelectDecoder();
 
   // Called when |decoder_selector| selected the |selected_decoder|.
   // |decrypting_demuxer_stream| was also populated if a DecryptingDemuxerStream
@@ -200,6 +200,8 @@ class MEDIA_EXPORT DecoderStream {
 
   DemuxerStream* stream_;
 
+  CdmContext* cdm_context_;
+
   std::unique_ptr<DecoderSelector<StreamType>> decoder_selector_;
 
   std::unique_ptr<Decoder> decoder_;