am 14e8e988: am 7d973514: Merge change 27449 into eclair

Merge commit '14e8e988cfdd01b665f5b49fb6f95a6c11ce3660'

* commit '14e8e988cfdd01b665f5b49fb6f95a6c11ce3660':
  Always consider m4a files as audio, even when they contain a video track.