Address ASAN complaint

TBR=bsalomon@google.com
Change-Id: Ic3b1f328a84d58939ff55b38cbc1fd4bd29ad5c6
Reviewed-on: https://skia-review.googlesource.com/22482
Reviewed-by: Robert Phillips <robertphillips@google.com>
Commit-Queue: Robert Phillips <robertphillips@google.com>
2 files changed