ref: 892e23a5badc2d929b7f179adc00c28820618681
parent: 34168287ede09b9e4f30c40265d3d2662527bbb4
author: Jim Bankoski <jimbankoski@google.com>
date: Mon Jan 9 04:23:34 EST 2012
vp8d - function to check if a reference frame is used. Change-Id: Id683b4d7f46ffa99145fc4b824c7232ab4182f21