Squash commits of the following patches, cherry-picked from other branch - do not merge.

o Prepare for publishing MediaMetadataRetriever as public API
  step one:
  o replaced captureFrame with getFrameAtTime
  o removed getMode

o Replace MediaMetadataRetriever.captureFrame() with MediaMetadataRetriever.getFrameAtTime()
  as part of the preparation for publishing MediaMetadataRetriever as public Java API

o Remove captureFrame from MediaMetadataRetriever.java class
  It has been replaced by getFrameAtTime() method

o Replace extractAlbumArt() with getEmbeddedPicture() in MediaMetadataRetriever.java

o Publish MediaMetadataRetriever.java as public API
  o Removed setMode() methods and related mode constants
  o Removed some of the unused the metadata keys
  o Updated the javadoc
  o part of a multi-project change.

bug - 3309041

Change-Id: I2efb6e8b8d52897186b016cb4efda6862f5584c4
diff --git a/media/libmediaplayerservice/MetadataRetrieverClient.h b/media/libmediaplayerservice/MetadataRetrieverClient.h
index 4aab94f..b834715 100644
--- a/media/libmediaplayerservice/MetadataRetrieverClient.h
+++ b/media/libmediaplayerservice/MetadataRetrieverClient.h
@@ -43,9 +43,7 @@
     virtual void                    disconnect();
     virtual status_t                setDataSource(const char *url);
     virtual status_t                setDataSource(int fd, int64_t offset, int64_t length);
-    virtual status_t                setMode(int mode);
-    virtual status_t                getMode(int* mode) const;
-    virtual sp<IMemory>             captureFrame();
+    virtual sp<IMemory>             getFrameAtTime(int64_t timeUs, int option);
     virtual sp<IMemory>             extractAlbumArt();
     virtual const char*             extractMetadata(int keyCode);
 
@@ -60,7 +58,6 @@
     mutable Mutex                          mLock;
     sp<MediaMetadataRetrieverBase>         mRetriever;
     pid_t                                  mPid;
-    int                                    mMode;
 
     // Keep the shared memory copy of album art and capture frame (for thumbnail)
     sp<IMemory>                            mAlbumArt;