In ForbidsClientSideElementArrayBuffer we test that WebGL Compatibility
returns a GL_INVALID_OPERATION but on NVIDIA Shield, the pointer had the
top bit set and caused a GL_INVALID_VALUE to be generated instead. Use a
intptr_t(1) for indices to test the correct error.

BUG=angleproject:1523

Change-Id: I1497694264befa14b2b6df167b4f20fdbb707983
Reviewed-on: https://chromium-review.googlesource.com/452547Reviewed-by: Geoff Lang <geofflang@chromium.org>
Reviewed-by: Yuly Novikov <ynovikov@chromium.org>
Commit-Queue: Corentin Wallez <cwallez@chromium.org>