Roll external/skia 2ef3b0fe3..65048139b (1 commits)

https://skia.googlesource.com/skia.git/+log/2ef3b0fe3..65048139b

2017-08-10 robertphillips@google.com Remove accessRenderTarget calls in service of binding stencil buffer

Test: Presubmit checks will test this change.
Change-Id: I9f6e783d6e154f218bc24f8f8d28fef68eb1354f