ref: 7ba6a676f54202b27e408e8d79086faa082eecb5
parent: 0c2ee67ad60fd53502edacb584f8973e2af6a5f7
parent: 61c5e94e228993bee187b11e415d3e7c4ac9286d
author: Yaowu Xu <yaowu@google.com>
date: Tue Jan 6 12:31:13 EST 2015
Merge "Use -1 consistently as invalid buffer idx"