remove mention of SkMetaData

Bug: skia:
Change-Id: I0f3fff0d29192e5ce9f1504ed54d032f9ffee77c
Reviewed-on: https://skia-review.googlesource.com/c/189285
Reviewed-by: Mike Reed <reed@google.com>
Commit-Queue: Mike Reed <reed@google.com>
Auto-Submit: Mike Reed <reed@google.com>
1 file changed