SharedFences are now only used by CommandQueue so move fence recycler
to live there instead of RendererVk.

Bug: b/170312581
Change-Id: Ib055ec50fbebe675a0064e1059089720e63b96b3
Reviewed-on: https://chromium-review.googlesource.com/c/angle/angle/+/2551792
Commit-Queue: Courtney Goeltzenleuchter <courtneygo@google.com>
Reviewed-by: Tim Van Patten <timvp@google.com>
Reviewed-by: Jamie Madill <jmadill@chromium.org>