Generalize AesDecryptor to make it more spec compliant.

media/filters/chunk_demuxer_client.h

Index: media/filters/chunk_demuxer_client.h
diff --git a/media/filters/chunk_demuxer_client.h b/media/filters/chunk_demuxer_client.h
index 3fbe6e351d00e5705cd26e0a44595400e95cf57f..4ac2f78e08e19577dd1f6b179190716279fa0425 100644
--- a/media/filters/chunk_demuxer_client.h
+++ b/media/filters/chunk_demuxer_client.h
@@ -25,7 +25,11 @@ class ChunkDemuxerClient {
   // A decryption key associated with |init_data| may be needed to decrypt the
   // media being demuxed before decoding. Note that the demuxing itself does not
   // need decryption.
-  virtual void KeyNeeded(scoped_array<uint8> init_data, int init_data_size) = 0;
+  virtual void DemuxerNeedKey(scoped_array<uint8> init_data,
+                              int init_data_size) = 0;
+
+ protected:
+  virtual ~ChunkDemuxerClient() {}
 };
 
 }  // namespace media