Mojo C++ bindings: custom type mapping of map

mojo/public/cpp/bindings/struct_traits.h

 // Copyright 2015 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_STRUCT_TRAITS_H_
 #define MOJO_PUBLIC_CPP_BINDINGS_STRUCT_TRAITS_H_
 
 namespace mojo {
 
 // This must be specialized for any type |T| to be serialized/deserialized as
@@ skipping 12 matching lines @@
 //        Value or reference of the same type used in |MojomType|, or the
 //        following alternatives:
 //        - string:
 //          Value or reference of any type that has a StringTraits defined.
 //          Supported by default: base::StringPiece, std::string.
 //
 //        - array:
 //          Value or reference of any type that has an ArrayTraits defined.
 //          Supported by default: std::vector, WTF::Vector (in blink).
 //
+//        - map:
+//          Value or reference of any type that has a MapTraits defined.
+//          Supported by default: std::map.
+//
 //        - struct:
 //          Value or reference of any type that has a StructTraits defined.
 //
 //      During serialization, getters for string/struct/array/map/union fields
 //      are called twice (one for size calculation and one for actual
 //      serialization); while the others are called once.
 //
 //   2. A static Read() method to set the contents of a |T| instance from a
 //      |MojomType|DataView (e.g., if |MojomType| is test::Example, the data
 //      view will be test::ExampleDataView).
@@ skipping 89 matching lines @@
 //
 //     static bool Read(FooDataView data, CustomFoo* output);
 //   };
 //
 template <typename MojomType, typename T>
 struct StructTraits;
 
 }  // namespace mojo
 
 #endif  // MOJO_PUBLIC_CPP_BINDINGS_STRUCT_TRAITS_H_