Fix type error with Metal mod(vec, float) intrinsic.

The code didn't take into account that x and y might be different types.
(This bug was not actually harmful; type coercion allowed the code to
compile even with the wrong type. The float would be silently splatted
into a vec and the rest of the code would work as-is.)

Change-Id: Ib76bc733f76304e451ef9197421b4bc22e29e49c
Reviewed-on: https://skia-review.googlesource.com/c/skia/+/348888
Commit-Queue: Brian Osman <brianosman@google.com>
Reviewed-by: Brian Osman <brianosman@google.com>
Auto-Submit: John Stiles <johnstiles@google.com>
2 files changed