Fix path builder initial gen ID

kEmpty means 'empty path', we want 0 to recompute as needed.

Change-Id: Ia9b2eb4f8e4b73ab2d5c05721cc9189be3653acb
Reviewed-on: https://skia-review.googlesource.com/c/skia/+/307223
Commit-Queue: Florin Malita <fmalita@chromium.org>
Commit-Queue: Florin Malita <fmalita@google.com>
Reviewed-by: Mike Reed <reed@google.com>
2 files changed