Mojo: more idiomatic C++ bindings

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

Index: mojo/public/cpp/bindings/lib/bindings_internal.h
diff --git a/mojo/public/cpp/bindings/lib/bindings_internal.h b/mojo/public/cpp/bindings/lib/bindings_internal.h
index 4b847e71e3c8f7c98a70db1f2fe9f9b57332bf82..56ab6725141d11e78f7852c4183ac03d478e3d64 100644
--- a/mojo/public/cpp/bindings/lib/bindings_internal.h
+++ b/mojo/public/cpp/bindings/lib/bindings_internal.h
@@ -158,6 +158,43 @@ template <typename S> struct TypeTraits<InterfaceHandle<S> > {
 
 template <typename T> class ObjectTraits {};
 
+template<class T, T v>
+struct integral_constant {
+  static const T value = v;
+  typedef T value_type;
+  typedef integral_constant<T, v> type;
+};
+
+template <class T, T v> const T integral_constant<T, v>::value;
+
+typedef integral_constant<bool, true> true_type;
+typedef integral_constant<bool, false> false_type;
+
+template <class T> struct is_const : false_type {};
+template <class T> struct is_const<const T> : true_type {};
+
+// Types YesType and NoType are guaranteed such that sizeof(YesType) <
+// sizeof(NoType).
+typedef char YesType;
+
+struct NoType {
+  YesType dummy[2];
+};
+
+// A helper template to determine if given type is non-const move-only-type,
+// i.e. if a value of the given type should be passed via .Pass() in a
+// destructive way.
+template <typename T> struct IsMoveOnlyType {
+  template <typename U>
+  static YesType Test(const typename U::MoveOnlyTypeForCPP03*);
+
+  template <typename U>
+  static NoType Test(...);
+
+  static const bool value = sizeof(Test<T>(0)) == sizeof(YesType) &&
+                            !is_const<T>::value;
+};
+
 }  // namespace internal
 }  // namespace mojo