Implement support for the binary operator '%' in the translator.

BUG=angle:854

Change-Id: If116de132dc83d93255749b54c1919a75abcb65c
Reviewed-on: https://chromium-review.googlesource.com/236330
Tested-by: Gregoire Payen de La Garanderie <Gregory.Payen@imgtec.com>
Reviewed-by: Jamie Madill <jmadill@chromium.org>