Mojo C++ bindings: make mojo::Map<K,V> more friendly with std::map<K,V>.

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

Index: mojo/public/cpp/bindings/lib/map_serialization.h
diff --git a/mojo/public/cpp/bindings/lib/map_serialization.h b/mojo/public/cpp/bindings/lib/map_serialization.h
index 054cd5daa93825d85a15c32c9ccdde7f15685025..91210ee60fed9bc57ab354097a64c8e76855dc13 100644
--- a/mojo/public/cpp/bindings/lib/map_serialization.h
+++ b/mojo/public/cpp/bindings/lib/map_serialization.h
@@ -120,10 +120,9 @@ inline size_t GetSerializedSize_(const Map<MapKey, MapValue>& input) {
   size_t value_data_size = 0;
   for (auto it = input.begin(); it != input.end(); ++it) {
     key_data_size +=
-        internal::MapSerializer<MapKey, DataKey>::GetItemSize(it.GetKey());
+        internal::MapSerializer<MapKey, DataKey>::GetItemSize(it->first);
     value_data_size +=
-        internal::MapSerializer<MapValue, DataValue>::GetItemSize(
-            it.GetValue());
+        internal::MapSerializer<MapValue, DataValue>::GetItemSize(it->second);
   }
 
   return struct_overhead + key_base_size + key_data_size + value_base_size +