Add SCALED formats, which correspond to non-normalized integers, to Vulkan
format table.  Adjust test expectations accordingly.  For now these new
formats only work when the native Vulkan supports them.

BUG=angleproject:2405

Change-Id: Ia6fdcbec61774536e6396cf713e46f28f49585c1
Reviewed-on: https://chromium-review.googlesource.com/1110710
Commit-Queue: Frank Henigman <fjhenigman@chromium.org>
Reviewed-by: Jamie Madill <jmadill@chromium.org>