Add the ability to dynamicaly register MediaPlayer types.

Add the ability to dynamically register low level MediaPlayer
factories which will be probed at setDataSource time to determine the
proper MediaPlayerBase to instantiate.

This change is in preparation for moving libaah_rtp out of
frameworks/base and into phantasm platform directory.

Change-Id: Icf8904db3ab9e3c85df6e780d5546d9988cb9076
Signed-off-by: John Grossman <johngro@google.com>
diff --git a/include/media/MediaPlayerInterface.h b/include/media/MediaPlayerInterface.h
index a70fe8c..0498ed1 100644
--- a/include/media/MediaPlayerInterface.h
+++ b/include/media/MediaPlayerInterface.h
@@ -154,12 +154,15 @@
     virtual status_t    getParameter(int key, Parcel *reply) = 0;
 
     // Right now, only the AAX TX player supports this functionality.  For now,
-    // provide a default implementation which indicates a lack of support for
-    // this functionality to make life easier for all of the other media player
+    // provide default implementations which indicate a lack of support for this
+    // functionality to make life easier for all of the other media player
     // maintainers out there.
     virtual status_t setRetransmitEndpoint(const struct sockaddr_in* endpoint) {
         return INVALID_OPERATION;
     }
+    virtual status_t getRetransmitEndpoint(struct sockaddr_in* endpoint) {
+        return INVALID_OPERATION;
+    }
 
     // Invoke a generic method on the player by using opaque parcels
     // for the request and reply.