Fix MSAN error in test

Bug: skia:
Change-Id: I27afd02b3383e259101a856630d04566fdf7a994
Reviewed-on: https://skia-review.googlesource.com/11407
Reviewed-by: Matt Sarett <msarett@google.com>
Reviewed-by: Jim Van Verth <jvanverth@google.com>
Commit-Queue: Matt Sarett <msarett@google.com>
1 file changed