remove old clipping flags

BUG=skia:

Change-Id: Ic80d918439af27d22bdd101124b72d3182baddc6
NOTRY=True
Reviewed-on: https://skia-review.googlesource.com/5920
Reviewed-by: Mike Reed <reed@google.com>
Commit-Queue: Mike Reed <reed@google.com>
1 file changed