rm unused fields

Change-Id: I70c7c4769e0a8d95b590a85fab34529041f8af8a
Reviewed-on: https://skia-review.googlesource.com/c/skia/+/220841
Reviewed-by: Mike Klein <mtklein@google.com>
Commit-Queue: Mike Klein <mtklein@google.com>
1 file changed