Unlike DSLPossibleExpression, this was only used in a few rare places,
so it was much easier to remove.
Change-Id: I483dc061691f89d3e808d5bbc23c500bc57b680a
Reviewed-on: https://skia-review.googlesource.com/c/skia/+/542662
Reviewed-by: Ethan Nicholas <ethannicholas@google.com>
Commit-Queue: John Stiles <johnstiles@google.com>
Reviewed-by: Brian Osman <brianosman@google.com>