ES only has the float versions.

BUG=angleproject:1145

Change-Id: I6c96b553d20e8aa160f68fe1b3fa0200d64108a3
Reviewed-on: https://chromium-review.googlesource.com/296361Reviewed-by: Jamie Madill <jmadill@chromium.org>
Tested-by: Geoff Lang <geofflang@chromium.org>