Fix various shader translator validation errors related to uniform
buffers and naming.

Bug: angleproject:3459
Test: angle_deqp_khr_gles3_tests
Change-Id: Iaa66b61e91c8f38ec7cccb43d71be9ba3cd83da3
Reviewed-on: https://chromium-review.googlesource.com/c/angle/angle/+/1684302
Commit-Queue: Tim Van Patten <timvp@google.com>
Reviewed-by: Shahbaz Youssefi <syoussefi@chromium.org>