apichanges: fix 2 wrong hashes

Signed-off-by: Michael Niedermayer <michaelni@gmx.at>
Adding AlphaMode element to Matroska Parser

Adding support for parsing AlphaMode element in the Track header
and export that information as a metadata tag. This flag indicates
presence of alpha channel data in BlockAdditional element.

Signed-off-by: Vignesh Venkatasubramanian <vigneshv@google.com>
Signed-off-by: Michael Niedermayer <michaelni@gmx.at>