Use signature for closure name instead of type.
Use signature instead of type to decide to use a runtime builtin comparator.
Remove trailing skips from signatures.
Change-Id: I73b2dcd3c6e2f1b2857985e14c24b290941b3ca3
Reviewed-on: https://go-review.googlesource.com/c/go/+/725604
LUCI-TryBot-Result: Go LUCI <golang-scoped@luci-project-accounts.iam.gserviceaccount.com> Reviewed-by: Cuong Manh Le <cuong.manhle.vn@gmail.com> Reviewed-by: Dmitri Shuralyov <dmitshur@google.com> Reviewed-by: Keith Randall <khr@google.com>