builtin: document clear is a no-op if its argument's value is nil
Just like the builtin function delete's comment does.
Change-Id: Id94a3aaa03c7b09594bae2b1af901d9060d9e255
GitHub-Last-Rev:
30cbebca96d9099f67a7dfc7650357aa19d6b810
GitHub-Pull-Request: golang/go#70801
Reviewed-on: https://go-review.googlesource.com/c/go/+/635535
Reviewed-by: Carlos Amedee <carlos@golang.org>
Reviewed-by: Keith Randall <khr@golang.org>
LUCI-TryBot-Result: Go LUCI <golang-scoped@luci-project-accounts.iam.gserviceaccount.com>
Reviewed-by: Keith Randall <khr@google.com>
Auto-Submit: Keith Randall <khr@golang.org>