Fix flutter compile bot

BUG=skia:6310

Change-Id: I540ea1b8a4e4c4faa8fa0f5550f25023763c3fea
Reviewed-on: https://skia-review.googlesource.com/9135
Reviewed-by: Eric Boren <borenet@google.com>
Commit-Queue: Ravi Mistry <rmistry@google.com>
3 files changed