BUG=angleproject:1523
BUG=668223
TEST=conformance/more/functions/copyTexImage2DBadArgs.html

Change-Id: I5fbf4f99fa941c356ecb57d67dd47a33741ce189
Reviewed-on: https://chromium-review.googlesource.com/418944Reviewed-by: Jamie Madill <jmadill@chromium.org>
Reviewed-by: Corentin Wallez <cwallez@chromium.org>
Commit-Queue: Geoff Lang <geofflang@chromium.org>