BUG=angleproject:1161

This is a continuation of the dirty bit refactor

Change-Id: I78ab046aaeb7de6dd288433c86e6524dcb2d6a66
Reviewed-on: https://chromium-review.googlesource.com/312837Reviewed-by: Geoff Lang <geofflang@chromium.org>
Tryjob-Request: Dian Xiang <dianx@google.com>
Tested-by: Dian Xiang <dianx@google.com>