Create mojom and StructTraits for ui/display/types/display_mode.cc

ui/ozone/common/mojo/ozone_gpu_struct_traits_test.mojom

Index: ui/ozone/common/mojo/ozone_gpu_struct_traits_test.mojom
diff --git a/ui/ozone/common/mojo/ozone_gpu_struct_traits_test.mojom b/ui/ozone/common/mojo/ozone_gpu_struct_traits_test.mojom
new file mode 100644
index 0000000000000000000000000000000000000000..0445db77e3d2076adce025de3bc1f6bcf3c422e6
--- /dev/null
+++ b/ui/ozone/common/mojo/ozone_gpu_struct_traits_test.mojom
@@ -0,0 +1,12 @@
+// Copyright 2017 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 ui.mojom;
+
+import "ui/ozone/common/mojo/display_mode_params.mojom";
+
+interface OzoneGpuStructTraitsTest {
+  [Sync]
+  EchoDisplayModeParams(DisplayModeParams in) => (DisplayModeParams out);
+};