Add bench for SkDDLRecorder detach

On Windows I'm getting:

curr/maxrss	loops	min	median	mean	max	stddev	samples   	config	bench
  33/38  MB	1495	2.62us	2.65us	2.66us	2.72us	1%	.o.o.oO.OO	gl	DDLRecorder

Change-Id: I529e6ac612c455915c166472124b08647eb7bffd
Reviewed-on: https://skia-review.googlesource.com/c/skia/+/241039
Reviewed-by: Brian Salomon <bsalomon@google.com>
Commit-Queue: Robert Phillips <robertphillips@google.com>
2 files changed