gofmt: add else test

R=gri
CC=golang-dev
https://golang.org/cl/4978065

src/cmd/gofmt/gofmt_test.go

@@ -73,6 +73,7 @@ var tests = []struct {
 	{"gofmt.go", ""},
 	{"gofmt_test.go", ""},
 	{"testdata/composites.input", "-s"},
+	{"testdata/old.input", ""},
 	{"testdata/rewrite1.input", "-r=Foo->Bar"},
 	{"testdata/rewrite2.input", "-r=int->bool"},
 	{"testdata/stdin*.input", "-stdin"},

src/cmd/gofmt/testdata/old.golden

+package P
+
+func f() {
+	if x {
+		y
+	} else {
+		z
+	}
+}

src/cmd/gofmt/testdata/old.input

+package P
+
+func f() {
+	if x {
+		y
+	} else
+		z
+}