Handle the corner case when VP8LDecodeImage() method is called with an invalid
header data. The lossless decoding doesn't support incremental mode yet.
Return the error status as BITSTREAM error in case not all pixels are decoded
with the provided bit-stream. Also added asserts in the VP8LDecodeImage() method
to validate the decoder header with appropriate/valid data for huffman trees
(htree_groups_ etc).
(cherry picked from commit e0a9932161)
Change-Id: Ibac9fcfc4bd0a2c5f624bb9d4a2b9f6459aa19ea
3740f7d4c6