Improves ValidateVertexShaderAttributeTypeMatch by storing vertex
attributes types into masks for quick comparisons when needed. This shows
2% improvement to glDrawElements for the aquarium workload.

BUG=angleproject:2202

Change-Id: I87fa3d30c3d8cdba6dfd936cd1a41fd27b1c6b77
Reviewed-on: https://chromium-review.googlesource.com/814795
Commit-Queue: Jamie Madill <jmadill@chromium.org>
Reviewed-by: Geoff Lang <geofflang@chromium.org>