Fix java bindings with array of maps.

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

 // 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.
 
 [JavaPackage="org.chromium.mojo.bindings.test.mojom.test_structs"]
 module mojo.test;
 
 import "mojo/public/interfaces/bindings/tests/rect.mojom";
 
 struct NamedRegion {
@@ skipping 118 matching lines @@
 // Used to verify that some common or difficult value types can be encoded and
 // decoded successfully.
 
 struct MapValueTypes {
   map<string, array<string>> f0;
   map<string, array<string>?> f1;
   map<string, array<string?>> f2;
   map<string, array<string, 2>> f3;
   map<string, array<array<string, 2>?>> f4;
   map<string, array<array<string, 2>, 1>> f5;
-  /* Disabled until Java bindings worked correctly.
   map<string, Rect?> f6;
   map<string, map<string, string>> f7;
   map<string, array<map<string, string>>> f8;
-  */
 };