Mojo C++ bindings: more consistent Clone() and Equals().

mojo/public/interfaces/bindings/tests/test_unions.mojom

 // Copyright 2014 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.
 
 module mojo.test;
 
 enum AnEnum {
   FIRST, SECOND
 };
 
@@ skipping 20 matching lines @@
 };
 
 union ObjectUnion {
   int8   f_int8;
   string f_string;
   DummyStruct f_dummy;
   DummyStruct? f_nullable;
   array<int8> f_array_int8;
   map<string, int8> f_map_int8;
   PodUnion f_pod_union;
+  // Test that Clone() is defined after SmallStruct is declared.
+  array<SmallStruct> f_small_structs;
 };
 
 union HandleUnion {
   handle f_handle;
   handle<message_pipe> f_message_pipe;
   handle<data_pipe_consumer> f_data_pipe_consumer;
   handle<data_pipe_producer> f_data_pipe_producer;
   handle<shared_buffer> f_shared_buffer;
   SmallCache f_small_cache;
 };
@@ skipping 42 matching lines @@
 };
 
 union OldUnion {
   int8 f_int8;
 };
 
 union NewUnion {
   int8 f_int8;
   int16 f_int16;
 };