Switch to use MediaMetadataRetriever to generate the project thumbnail when the first media item is a MediaVideoItem

o This patch allows us to use the logic from MediaMetadataRetriever to extract a thumbnail instead of extracting
  the thumbnail from a fixed position (@500 ms).

Change-Id: I81e8378d9bed80894cc622479679021dce3d52e5
related-to-bug: 3485609
1 file changed