ref: 943981abc4f0e891386c293b843d037d8bdebf15
parent: bea361a1f09f57698b360e31dafaea854c9988fc
author: Sijia Chen <sijchen@cisco.com>
date: Mon Feb 9 08:50:31 EST 2015
fix a nal generation for simulcast avc and add nal-type check for simulcast avc UT