ref: c39526da8a88facd9326ce68a6ad5ad250e096dc
parent: 327c9bb1da0e0ceac4293ab42fa8c25e8f1706c9
author: Jerome Jiang <jianj@google.com>
date: Fri May 26 12:20:49 EDT 2017
Write skin map of vp8 skin detection for debug. Change-Id: Ica1b4e918aa759cd0ce65920f9d88452bbf9e3b4