We would allocate this texture for devices that don't need it. Instead
do this lazily. This was showing up in the profiles for the MotionMark
benchmark, possibly due to re-creating the surface.

BUG=angleproject:1155

Change-Id: I28b5eda29e21899fc8afef054e1b8063e3cc2e00
Reviewed-on: https://chromium-review.googlesource.com/655479Reviewed-by: Geoff Lang <geofflang@chromium.org>
Commit-Queue: Jamie Madill <jmadill@chromium.org>