Mojo: Unify the disparate source and header files into 3

mojo/public/bindings/generators/cpp_templates/interface_serialization.cc-template

Index: mojo/public/bindings/generators/cpp_templates/interface_serialization.cc-template
diff --git a/mojo/public/bindings/generators/cpp_templates/interface_serialization.cc-template b/mojo/public/bindings/generators/cpp_templates/interface_serialization.cc-template
deleted file mode 100644
index cae063a17c94d2da90ee1aadbb7b255ecbea64c8..0000000000000000000000000000000000000000
--- a/mojo/public/bindings/generators/cpp_templates/interface_serialization.cc-template
+++ /dev/null
@@ -1,21 +0,0 @@
-// Copyright $YEAR The Chromium Authors. All rights reserved.
-// Use of this source code is governed by a BSD-style license that can be
-// found in the LICENSE file.
-
-#include "$HEADER"
-
-namespace $NAMESPACE {
-namespace internal {
-
-$IMPLEMENTATIONS
-
-}  // namespace internal
-}  // namespace sample
-
-namespace mojo {
-namespace internal {
-
-$SERIALIZATIONS
-
-}  // namespace internal
-}  // namespace mojo