Remove getIndexRange call from ValidateDrawRangeElementsBaseVertex
Remove getIndexRange call from ValidateDrawRangeElementsBaseVertex

This is essentially the same commit as fed0dda, but with the BaseVertex variant.

Bug: angleproject:4373
Change-Id: I2d6fe46a0e8ce5faa8c92d4db6909f8cabd9692f
Reviewed-on: https://chromium-review.googlesource.com/c/angle/angle/+/2032972
Reviewed-by: Jamie Madill <7e492b4f1c8458024932de3ba475cbf015424c30@chromium.org>
Reviewed-by: Charlie Lao <2661ca4ca24c371418789adbc76dfb4875087223@google.com>
Commit-Queue: Jamie Madill <7e492b4f1c8458024932de3ba475cbf015424c30@chromium.org>

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