gc: insert semicolon at EOF if needed

R=ken2, gri
CC=golang-dev
https://golang.org/cl/2208053
diff --git a/test/eof.go b/test/eof.go
new file mode 100644
index 0000000..81f9fd0
--- /dev/null
+++ b/test/eof.go
@@ -0,0 +1,9 @@
+// $G $D/$F.go
+
+// Copyright 2010 The Go Authors.  All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+// No newline at the end of this file.
+
+package main
\ No newline at end of file