remove (unused) duplicate field of fUniqueID

Change-Id: I0e9fe683950ec4905a8bdaa2e965f7bc0287b91a
Reviewed-on: https://skia-review.googlesource.com/c/skia/+/295918
Reviewed-by: Brian Osman <brianosman@google.com>
Commit-Queue: Mike Reed <reed@google.com>
2 files changed