Adding extensions that are not native driver extensions would cause
surface creation to fail.

BUG=angleproject:1635

Change-Id: I2f683ee0560e463aa06f3ba92d0bf3f3d8c8927d
Reviewed-on: https://chromium-review.googlesource.com/701602
Commit-Queue: Geoff Lang <geofflang@chromium.org>
Reviewed-by: Yuly Novikov <ynovikov@chromium.org>