Catch infinite numbers in computeMatrices

Bug: skia:7433
Change-Id: I54ec095a2e6a3596f99e3659c947c6489a68ff47
Reviewed-on: https://skia-review.googlesource.com/118164
Reviewed-by: Ben Wagner <bungeman@google.com>
Commit-Queue: Ben Wagner <bungeman@google.com>
1 file changed