width or height is 0.

BUG=angleproject:990

Change-Id: I9fbdd3d341d3f6fa42dfb39950e6b2d3204c4c9b
Reviewed-on: https://chromium-review.googlesource.com/267415Reviewed-by: Geoff Lang <geofflang@chromium.org>
Tested-by: Régis Fénéon <regis.feneon@gmail.com>
Reviewed-by: Jamie Madill <jmadill@chromium.org>