[ios Mojo] iOS facade class for Mojo API.

ios/web/test/mojo_test.mojom

Index: ios/web/test/mojo_test.mojom
diff --git a/ios/web/test/mojo_test.mojom b/ios/web/test/mojo_test.mojom
new file mode 100644
index 0000000000000000000000000000000000000000..91cb201c5f0b982fb2092cfca15a5657fe6c9cd7
--- /dev/null
+++ b/ios/web/test/mojo_test.mojom
@@ -0,0 +1,15 @@
+// Copyright 2016 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.
+
+struct NativeMessageResultMojo {
+  string message;
+};
+
+interface TestUIHandlerMojo {
+  HandleJsMessage(string message, TestPage page);
+};
+
+interface TestPage {
+  HandleNativeMessage(NativeMessageResultMojo result);
+};