Drop the ref on the GrOpList's target in makeClosed (take 2)

Bug: 729233

TBR=bsalomon@google.com

Change-Id: I5c9a0cb793c7c6564ad355a4a63b29fdc12f6cd7
Reviewed-on: https://skia-review.googlesource.com/19860
Reviewed-by: Robert Phillips <robertphillips@google.com>
Commit-Queue: Robert Phillips <robertphillips@google.com>
4 files changed