Some dEQP tests call eglTerminate twice on the same display and cause crashes.

BUG=angleproject:2546

Change-Id: I3118e07aec19a28ad2b76fc2705be5b0bea37857
Reviewed-on: https://chromium-review.googlesource.com/1066467Reviewed-by: Geoff Lang <geofflang@chromium.org>
Commit-Queue: Geoff Lang <geofflang@chromium.org>