NVidia drivers have no trouble clearing textures without showing
corruption. AMD ones do.

Intel drivers that have trouble have been relegated to the DX9 runtime
by Chromium.

Bug: angleproject:4460
Change-Id: I9ffbfa041e0f7ef8e05edcc14274bf9530eafae3
Reviewed-on: https://chromium-review.googlesource.com/c/angle/angle/+/2147821Reviewed-by: Geoff Lang <geofflang@chromium.org>
Reviewed-by: Jamie Madill <jmadill@chromium.org>
Commit-Queue: Rafael Cintron <rafael.cintron@microsoft.com>