builtin: correct comment on builtin function delete().
Delete on a nil map is now a no-op.
R=golang-dev, bradfitz
CC=golang-dev
https://golang.org/cl/6938054
diff --git a/src/pkg/builtin/builtin.go b/src/pkg/builtin/builtin.go
index a30943b..91d263a 100644
--- a/src/pkg/builtin/builtin.go
+++ b/src/pkg/builtin/builtin.go
@@ -124,8 +124,8 @@
func copy(dst, src []Type) int
// The delete built-in function deletes the element with the specified key
-// (m[key]) from the map. If there is no such element, delete is a no-op.
-// If m is nil, delete panics.
+// (m[key]) from the map. If m is nil or there is no such element, delete
+// is a no-op.
func delete(m map[Type]Type1, key Type)
// The len built-in function returns the length of v, according to its type:
