Remove redundant check from constant-value detection code.

The last if check in this loop was unnecessary. It was an exact
duplicate of the first check at the top of the loop.

Change-Id: I08adc4f6df8577d168ae965220c0d9ddceb91121
Reviewed-on: https://skia-review.googlesource.com/c/skia/+/441240
Auto-Submit: John Stiles <johnstiles@google.com>
Commit-Queue: Ethan Nicholas <ethannicholas@google.com>
Reviewed-by: Ethan Nicholas <ethannicholas@google.com>
1 file changed