Need to rename these so that they don't conflict
with GL function declarations

Bug: angleproject:3702
Change-Id: Iefe490cb53a384c45f0d0024321deda43b461bcc
Reviewed-on: https://chromium-review.googlesource.com/c/angle/angle/+/1704214Reviewed-by: Jonah Ryan-Davis <jonahr@google.com>
Reviewed-by: Jamie Madill <jmadill@chromium.org>
Commit-Queue: Clemen Deng <clemendeng@google.com>