VideoPlayerActivity: do not add callbacks for local surfaces while in presentation mode

Presentation mode did not work with the full HW acceleration mode
since MediaCodec was rendering to the local surface instead of the
remote surface.

vlc-android/src/org/videolan/vlc/gui/video/VideoPlayerActivity.java

@@ -351,13 +351,15 @@ public class VideoPlayerActivity extends Activity implements IVideoPlayer {
         } else {
             mSurfaceHolder.setFormat(PixelFormat.RGBX_8888);
         }
-        mSurfaceHolder.addCallback(mSurfaceCallback);
 
         mSubtitlesSurface = (SurfaceView) findViewById(R.id.subtitles_surface);
         mSubtitlesSurfaceHolder = mSubtitlesSurface.getHolder();
         mSubtitlesSurfaceHolder.setFormat(PixelFormat.RGBA_8888);
         mSubtitlesSurface.setZOrderMediaOverlay(true);
-        mSubtitlesSurfaceHolder.addCallback(mSubtitlesSurfaceCallback);
+        if (mPresentation == null) {
+            mSurfaceHolder.addCallback(mSurfaceCallback);
+            mSubtitlesSurfaceHolder.addCallback(mSubtitlesSurfaceCallback);
+        }
 
         mSeekbar = (SeekBar) findViewById(R.id.player_overlay_seekbar);
         mSeekbar.setOnSeekBarChangeListener(mSeekListener);