The current code rejects any shaders that use more than the caps
allow, but a bug would crash us before the check. We don't support
aliasing in shaders that use a lot of uniforms because this
causes problems with the D3D back-end, currently. This changes the
crash in the dEQP aliasing tests to a link error.

See dEQP-GLES2.functional.attribute_location.bind_aliasing.*

BUG=angleproject:901

Change-Id: I6906d3345abe9f89cfa0aa6cec4be26b5b2851d0
Reviewed-on: https://chromium-review.googlesource.com/266928Tested-by: Jamie Madill <jmadill@chromium.org>
Reviewed-by: Geoff Lang <geofflang@chromium.org>
Reviewed-by: Brandon Jones <bajones@chromium.org>