Remove DisplayStructTraitsTest interface.

ui/display/mojo/display_struct_traits_test.mojom

Index: ui/display/mojo/display_struct_traits_test.mojom
diff --git a/ui/display/mojo/display_struct_traits_test.mojom b/ui/display/mojo/display_struct_traits_test.mojom
deleted file mode 100644
index ba18e611d81b5b20f2a6d97fe6e0681f674fd4ea..0000000000000000000000000000000000000000
--- a/ui/display/mojo/display_struct_traits_test.mojom
+++ /dev/null
@@ -1,36 +0,0 @@
-// 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.
-
-module display.mojom;
-
-import "ui/display/mojo/display.mojom";
-import "ui/display/mojo/display_constants.mojom";
-import "ui/display/mojo/display_layout.mojom";
-import "ui/display/mojo/display_mode.mojom";
-import "ui/display/mojo/display_snapshot_mojo.mojom";
-import "ui/display/mojo/gamma_ramp_rgb_entry.mojom";
-
-interface DisplayStructTraitsTest {
-  [Sync]
-  EchoDisplay(Display in) => (Display out);
-
-  [Sync]
-  EchoDisplayMode(DisplayMode in) => (DisplayMode out);
-
-  [Sync]
-  EchoDisplaySnapshotMojo(DisplaySnapshotMojo in) => (DisplaySnapshotMojo
-    out);
-
-  [Sync]
-  EchoDisplayPlacement(DisplayPlacement in) => (DisplayPlacement out);
-
-  [Sync]
-  EchoDisplayLayout(DisplayLayout in) => (DisplayLayout out);
-
-  [Sync]
-  EchoHDCPState(HDCPState in) => (HDCPState out);
-
-  [Sync]
-  EchoGammaRampRGBEntry(GammaRampRGBEntry in) => (GammaRampRGBEntry out);
-};