guard against NaN in path is rect

Recent rewrite of SkPath::isRect() did not check against
sequences with NaN and infinity.

R=kjlubick@google.com

Bug: oss-fuzz:7882
Change-Id: I9315f68e4c53c37fda819adc6d57d6b3e3acc1c6
Reviewed-on: https://skia-review.googlesource.com/122783
Commit-Queue: Cary Clark <caryclark@google.com>
Commit-Queue: Kevin Lubick <kjlubick@google.com>
Auto-Submit: Cary Clark <caryclark@google.com>
Reviewed-by: Kevin Lubick <kjlubick@google.com>
1 file changed