We will need these to implement a more secure version of hashing for the
program binary cache. These versions of lightly modified from the Chrome
versions to make compilation simpler.

BUG=angleproject:1897

Change-Id: Ibcadb56c2316e3f39655a07fa28b5fbd6103e452
Reviewed-on: https://chromium-review.googlesource.com/550000Reviewed-by: Corentin Wallez <cwallez@chromium.org>
Commit-Queue: Jamie Madill <jmadill@chromium.org>