Add Flutter as a Skia customer

Change-Id: Ida222fcd4fafc7fc6259f5f5943eff8d0475236f
No-Try: true
Docs-Preview: https://skia.org/?cl=302081
Reviewed-on: https://skia-review.googlesource.com/c/skia/+/302081
Auto-Submit: Yuqian Li <liyuqian@google.com>
Commit-Queue: Heather Miller <hcm@google.com>
Reviewed-by: Heather Miller <hcm@google.com>
2 files changed