[bindings] Include copyright block in generated code for consistency.

Source/bindings/templates/callback_interface.cpp

Index: Source/bindings/templates/callback_interface.cpp
diff --git a/Source/bindings/templates/callback_interface.cpp b/Source/bindings/templates/callback_interface.cpp
index f82e789d2b1b909eafae2a545fa4d557561a18ac..82e716dde16cd85cf9f7aedeff27cc2d567ee94e 100644
--- a/Source/bindings/templates/callback_interface.cpp
+++ b/Source/bindings/templates/callback_interface.cpp
@@ -1,9 +1,4 @@
-// Copyright 2014 The Chromium Authors. All rights reserved.
-// Use of this source code is governed by a BSD-style license that can be
-// found in the LICENSE file.
-
-// This file has been auto-generated by {{code_generator}}. DO NOT MODIFY!
-
+{% include 'copyright_block.txt' %}
 #include "config.h"
 {% filter conditional(conditional_string) %}
 #include "{{v8_class}}.h"