webm_file,CheckCuesAlignmentList: reduce stack size fixes: shared/webm_file.cc:693:1: error: the frame size of 16752 bytes is larger than 16384 bytes Bug: b/150135466 Change-Id: Id9b6a52fb33108b3b310dd92ea56e77152545a0b PiperOrigin-RevId: 157805347