Verify that PolyTF parameters are finite after each step

Bug: oss-fuzz:8165
Change-Id: I9b4dbee12972b15f6af15d237d1c3a3d46495e68
Reviewed-on: https://skia-review.googlesource.com/126423
Auto-Submit: Brian Osman <brianosman@google.com>
Reviewed-by: Mike Klein <mtklein@chromium.org>
Commit-Queue: Brian Osman <brianosman@google.com>
4 files changed