Remove 0/x arithmetic simplification.

If x is a known compile-time constant value, it can already be optimized
to a final value.
If x is not known, it could be zero, and 0/0 should result in a NaN.

Change-Id: I643a7c6da0a43ec366235c4df39fc78d3b361de7
Reviewed-on: https://skia-review.googlesource.com/c/skia/+/441580
Reviewed-by: Brian Osman <brianosman@google.com>
Commit-Queue: Brian Osman <brianosman@google.com>
Commit-Queue: John Stiles <johnstiles@google.com>
Auto-Submit: John Stiles <johnstiles@google.com>
8 files changed