path: fix up bizarre test

The Join test was doing something remarkable and unnecessary instead of
just using ... on a slice. Maybe it was an editing relic.

Fix it by deleting the monstrosity.

Change-Id: I5b90c6d539d334a9c27e57d26dacd831721cfcfe
Reviewed-on: https://go-review.googlesource.com/20727Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>
Run-TryBot: Brad Fitzpatrick <bradfitz@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>

src/path/path_test.go

@@ -135,15 +135,9 @@ var jointests = []JoinTest{
 	{[]string{"", ""}, ""},
 }
 
-// join takes a []string and passes it to Join.
-func join(elem []string, args ...string) string {
-	args = elem
-	return Join(args...)
-}
-
 func TestJoin(t *testing.T) {
 	for _, test := range jointests {
-		if p := join(test.elem); p != test.path {
+		if p := Join(test.elem...); p != test.path {
 			t.Errorf("join(%q) = %q, want %q", test.elem, p, test.path)
 		}
 	}