abort if TF invert fails

GCC caught this when debugging the MIPS64/-O3 issue.
Kind of unrelated, but required to add a MIPS64/-O3 bot.

Change-Id: If3f656b301f6ae4335cf1d3839a88e58f3714ab2
Reviewed-on: https://skia-review.googlesource.com/c/162004
Commit-Queue: Mike Klein <mtklein@google.com>
Commit-Queue: Brian Osman <brianosman@google.com>
Auto-Submit: Mike Klein <mtklein@google.com>
Reviewed-by: Brian Osman <brianosman@google.com>
1 file changed