Snug the clip with path bounds inside SkAAClip

https://codereview.chromium.org/2482193004/ is related with this patch.

BUG=skia:

GOLD_TRYBOT_URL= https://gold.skia.org/search?issue=4636

Change-Id: Ibd6d64578e08c75a3cfcef45489afc9b59ad40be
Reviewed-on: https://skia-review.googlesource.com/4636
Commit-Queue: Yuqian Li <liyuqian@google.com>
Reviewed-by: Mike Reed <reed@google.com>
1 file changed