[automerger] Check NAL size before looking inside am: e0c020969d am: 8c4ae8057c am: 767a82a9d6 am: f7d9bba9b1 am: e04b7c8c06 am: 25e199f787 am: 93962ef505 am: 714148f6eb am: b6fdd7ee95 am: 3631c04dfa am: 68adda01b0 am: 68e58ff3bd
am: 078f1de778

Change-Id: Ia4ab7c252c8865e09879c2118739659b6dc6e4e8