Added some validation for uniforms and uniform blocks.

Fixes some failures in (only 1 failure left):
dEQP-GLES3.functional.negative_api.state*

Change-Id: I507c7e8784230f85b0d312d162e5ff82bdbd15ed
Reviewed-on: https://swiftshader-review.googlesource.com/14428Tested-by: Alexis Hétu <sugoi@google.com>
Reviewed-by: Nicolas Capens <nicolascapens@google.com>