This reverts commit 6541013b53.
Reason for revert: TSAN issues with GrFence, and crash in GrMtlPipelineStateBuilder::CreatePipelineState.
Original change's description:
> Remove ARC from Metal backend
>
> Change-Id: I5ab28f6eda3b37d1b82c94c7cc6eaa2ce59157da
> Reviewed-on: https://skia-review.googlesource.com/c/skia/+/311113
> Reviewed-by: Adlai Holler <adlai@google.com>
> Reviewed-by: John Stiles <johnstiles@google.com>
> Commit-Queue: Jim Van Verth <jvanverth@google.com>
TBR=jvanverth@google.com,bsalomon@google.com,adlai@google.com,johnstiles@google.com
Change-Id: I031629b483fc46de8bd3751253e5391c2ce87853
No-Presubmit: true
No-Tree-Checks: true
No-Try: true
Reviewed-on: https://skia-review.googlesource.com/c/skia/+/312843
Reviewed-by: Jim Van Verth <jvanverth@google.com>
Commit-Queue: Jim Van Verth <jvanverth@google.com>
36b86aff6b