Clarify the section in the "go" command notes that deals with the
changes to "go test -cover" for packages without tests, adding a note
that if a package has not tests and no executable code, you still get
a "package has no test files" diagnostic.
Fixes #65262.
Change-Id: Ie960871f9d5c1a1965090738644eace28fc3e156
Reviewed-on: https://go-review.googlesource.com/c/go/+/561337 Reviewed-by: Dmitri Shuralyov <dmitshur@golang.org> Reviewed-by: Dmitri Shuralyov <dmitshur@google.com>
LUCI-TryBot-Result: Go LUCI <golang-scoped@luci-project-accounts.iam.gserviceaccount.com> Reviewed-by: Chris Hines <chris.cs.guy@gmail.com>