This test exercises change signature refactoring handling of function values.

TODO(rfindley): use a literalization strategy to allow these references.

-- go.mod --
module unused.mod

go 1.18

-- a/a.go --
package a

func A(x, unused int) int { //@codeactionerr("unused", "unused", "refactor.rewrite", re"non-call function reference")
	return x
}

func _() {
	_ = A
}