Add scratch-only version of performDeferredCleanup

Change-Id: I5707d1da1b69ab1ffaa77d7a391a187ac3e8eba1
Reviewed-on: https://skia-review.googlesource.com/c/skia/+/417267
Commit-Queue: Michael Ludwig <michaelludwig@google.com>
Reviewed-by: Robert Phillips <robertphillips@google.com>
12 files changed