Remove SkPaint::getHash

This was a particularly bad hash (A == B didn't imply
hash(A) == hash(B)). It was also entirely unused.

Change-Id: Id923bf1035effce04e12b1cc01d1c6aa4d11fdb6
Reviewed-on: https://skia-review.googlesource.com/c/skia/+/419336
Commit-Queue: Brian Osman <brianosman@google.com>
Reviewed-by: Mike Reed <reed@google.com>
7 files changed