Make sure we add render target mem barriers after any last second copies

Bug: skia:
Change-Id: I67e6e6a026145ecbd7476fbf201ce07e053c337d
Reviewed-on: https://skia-review.googlesource.com/110622
Reviewed-by: Jim Van Verth <jvanverth@google.com>
Commit-Queue: Greg Daniel <egdaniel@google.com>
1 file changed