Extend math test to ensure our min/max/pin handle non-finites

Bug: skia:
Change-Id: I4fe544c32da071d161229b12f7b90a3296b0d499
Reviewed-on: https://skia-review.googlesource.com/112140
Reviewed-by: Mike Reed <reed@google.com>
Commit-Queue: Mike Reed <reed@google.com>
1 file changed