go/types/typeutil: add missing copyright notices

Change-Id: I101c033ffc20fde38b0f0b075f559aa10a6e43d0
Reviewed-on: https://go-review.googlesource.com/10772
Reviewed-by: Alan Donovan <adonovan@google.com>
diff --git a/go/types/typeutil/example_test.go b/go/types/typeutil/example_test.go
index 67ee34f..9e3ada7 100644
--- a/go/types/typeutil/example_test.go
+++ b/go/types/typeutil/example_test.go
@@ -1,3 +1,7 @@
+// Copyright 2014 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.
+
 package typeutil_test
 
 import (
diff --git a/go/types/typeutil/imports.go b/go/types/typeutil/imports.go
index 0f4a232..967fe1e 100644
--- a/go/types/typeutil/imports.go
+++ b/go/types/typeutil/imports.go
@@ -1,3 +1,7 @@
+// Copyright 2014 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.
+
 package typeutil
 
 import "golang.org/x/tools/go/types"
diff --git a/go/types/typeutil/imports_test.go b/go/types/typeutil/imports_test.go
index 6f207cf..8071ae1 100644
--- a/go/types/typeutil/imports_test.go
+++ b/go/types/typeutil/imports_test.go
@@ -1,3 +1,7 @@
+// Copyright 2014 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.
+
 package typeutil_test
 
 import (