Split the flush and finish commands into separate methods. Improves the readability of the implementations and more closely mirrors the GL commands. Change-Id: Ifa7bc55751d50271eb01fd87e4efdc69f00c2c48 Reviewed-on: https://chromium-review.googlesource.com/239845 Reviewed-by: Jamie Madill <jmadill@chromium.org> Reviewed-by: Brandon Jones <bajones@chromium.org> Tested-by: Geoff Lang <geofflang@chromium.org>