Defines MediaPlayer APIs to support multiple audio/video/timedtext
tracks.

o Newly introduced APIs are (MediaPlayer):
  getTrackInfo() / addExternalSource() / enableTrack() / disableTrack().

o Timed text tracks are supported only, for now.

o TODOs:
 - Define the audio/video behavior for enableTrack and disableTrack.
 - Refactoring AwesomePlayer / TimedTextDriver so that all types of
   track index can be managed in the correct order and be ready for
   supporting audio/video tracks.
   (MediaExtractor and MediaSource for text file might be necessary.)

Change-Id: Idb85e1b3f2ed49a64f377d05472dd6663ce94e07
diff --git a/include/media/mediaplayer.h b/include/media/mediaplayer.h
index 662dd13..a68ab4e 100644
--- a/include/media/mediaplayer.h
+++ b/include/media/mediaplayer.h
@@ -120,6 +120,9 @@
     MEDIA_INFO_NOT_SEEKABLE = 801,
     // New media metadata is available.
     MEDIA_INFO_METADATA_UPDATE = 802,
+
+    //9xx
+    MEDIA_INFO_TIMED_TEXT_ERROR = 900,
 };
 
 
@@ -140,9 +143,6 @@
 // The same enum space is used for both set and get, in case there are future keys that
 // can be both set and get.  But as of now, all parameters are either set only or get only.
 enum media_parameter_keys {
-    KEY_PARAMETER_TIMED_TEXT_TRACK_INDEX = 1000,                // set only
-    KEY_PARAMETER_TIMED_TEXT_ADD_OUT_OF_BAND_SOURCE = 1001,     // set only
-
     // Streaming/buffering parameters
     KEY_PARAMETER_CACHE_STAT_COLLECT_FREQ_MS = 1100,            // set only
 
@@ -155,6 +155,23 @@
     KEY_PARAMETER_PLAYBACK_RATE_PERMILLE = 1300,                // set only
 };
 
+// Keep INVOKE_ID_* in sync with MediaPlayer.java.
+enum media_player_invoke_ids {
+    INVOKE_ID_GET_TRACK_INFO = 1,
+    INVOKE_ID_ADD_EXTERNAL_SOURCE = 2,
+    INVOKE_ID_ADD_EXTERNAL_SOURCE_FD = 3,
+    INVOKE_ID_SELECT_TRACK = 4,
+    INVOKE_ID_UNSELECT_TRACK = 5,
+};
+
+// Keep MEDIA_TRACK_TYPE_* in sync with MediaPlayer.java.
+enum media_track_type {
+    MEDIA_TRACK_TYPE_UNKNOWN = 0,
+    MEDIA_TRACK_TYPE_VIDEO = 1,
+    MEDIA_TRACK_TYPE_AUDIO = 2,
+    MEDIA_TRACK_TYPE_TIMEDTEXT = 3,
+};
+
 // ----------------------------------------------------------------------------
 // ref-counted object for callbacks
 class MediaPlayerListener: virtual public RefBase