Disallow initializers on uniform variables

Bug: skia:11335
Change-Id: I88c952cbfe2d2c5920e17675da1674928f37b982
Reviewed-on: https://skia-review.googlesource.com/c/skia/+/371480
Reviewed-by: John Stiles <johnstiles@google.com>
Commit-Queue: Brian Osman <brianosman@google.com>
5 files changed