mojo: Allow circular dependencies between structs

mojo/public/cpp/bindings/lib/bindings_internal.h

 // Copyright 2013 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.
 
 #ifndef MOJO_PUBLIC_CPP_BINDINGS_LIB_BINDINGS_INTERNAL_H_
 #define MOJO_PUBLIC_CPP_BINDINGS_LIB_BINDINGS_INTERNAL_H_
 
 #include "mojo/public/cpp/bindings/lib/template_util.h"
+#include "mojo/public/cpp/bindings/struct_ptr.h"
 #include "mojo/public/cpp/system/core.h"
 
 namespace mojo {
 class String;
 
 namespace internal {
 template <typename T> class Array_Data;
 
 #pragma pack(push, 1)
 
@@ skipping 50 matching lines @@
 
 template <typename T, bool move_only = IsMoveOnlyType<T>::value>
 struct WrapperTraits;
 
 template <typename T> struct WrapperTraits<T, false> {
   typedef T DataType;
 };
 template <typename H> struct WrapperTraits<ScopedHandleBase<H>, true> {
   typedef H DataType;
 };
+template <typename S> struct WrapperTraits<StructPtr<S>, true> {
+  typedef typename S::Data_* DataType;
+};
+template <typename S> struct WrapperTraits<InlinedStructPtr<S>, true> {
+  typedef typename S::Data_* DataType;
+};
 template <typename S> struct WrapperTraits<S, true> {
   typedef typename S::Data_* DataType;
 };
 
 }  // namespace internal
 }  // namespace mojo
 
 #endif  // MOJO_PUBLIC_CPP_BINDINGS_LIB_BINDINGS_INTERNAL_H_