create outer forloop to support loops=-1

Change-Id: I1f76a798f3f95afb82ab739ab5343bf52b233c7d
Reviewed-on: https://skia-review.googlesource.com/c/skia/+/226079
Reviewed-by: Mike Reed <reed@google.com>
Commit-Queue: Mike Reed <reed@google.com>
Auto-Submit: Mike Reed <reed@google.com>
1 file changed