Generalize AesDecryptor to make it more spec compliant.

media/base/stream_parser.h

Index: media/base/stream_parser.h
diff --git a/media/base/stream_parser.h b/media/base/stream_parser.h
index 22fc0c21e82aee773cba921abbf57e0fa1a492fd..86db588e45cffa5d94506317b435ba5e19ecaf11 100644
--- a/media/base/stream_parser.h
+++ b/media/base/stream_parser.h
@@ -59,7 +59,7 @@ class MEDIA_EXPORT StreamParser {
   // Return value - True indicates that the initialization data is accepted.
   //                False if something was wrong with the initialization data
   //                and a parsing error should be signalled.
-  typedef base::Callback<bool(scoped_array<uint8>, int)> KeyNeededCB;
+  typedef base::Callback<bool(scoped_array<uint8>, int)> NeedKeyCB;
 
   // Initialize the parser with necessary callbacks. Must be called before any
   // data is passed to Parse(). |init_cb| will be called once enough data has
@@ -69,7 +69,7 @@ class MEDIA_EXPORT StreamParser {
                     const NewConfigCB& config_cb,
                     const NewBuffersCB& audio_cb,
                     const NewBuffersCB& video_cb,
-                    const KeyNeededCB& key_needed_cb) = 0;
+                    const NeedKeyCB& need_key_cb) = 0;
 
   // Called when a seek occurs. This flushes the current parser state
   // and puts the parser in a state where it can receive data for the new seek