[graphite] Add destination information to KeyContext

Bug: b/239959460
Change-Id: I2d065171d526d185a262fd93d66bff70c72f5b2f
Reviewed-on: https://skia-review.googlesource.com/c/skia/+/626237
Reviewed-by: James Godfrey-Kittle <jamesgk@google.com>
Commit-Queue: Robert Phillips <robertphillips@google.com>
11 files changed