Refactor uniform block test cases
Refactor uniform block test cases

The patch refactors cases that test a uniform block only containing
a large array member, which will be translated to StructuredBuffer
on D3D backend.

Bug: angleproject:3682
Change-Id: I3170a4c82896ce8895909db87c70b80656300383
Reviewed-on: https://chromium-review.googlesource.com/c/angle/angle/+/2489482
Commit-Queue: Jamie Madill <7e492b4f1c8458024932de3ba475cbf015424c30@chromium.org>
Reviewed-by: Jamie Madill <7e492b4f1c8458024932de3ba475cbf015424c30@chromium.org>
Reviewed-by: Jiajia Qin <18ef504dc2f2be7888c61ad30571995bf38d04e0@intel.com>

ppy/angle,ppy/angle,ppy/angle,ppy/angle