Sync GN tests with GYP build.

ui/events/BUILD.gn

 # 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.
 
 import("//build/config/ui.gni")
 import("//testing/test.gni")
 
 static_library("dom_keycode_converter") {
   sources = [
     "keycodes/dom/dom_code.h",
@@ skipping 373 matching lines @@
       "ozone/layout/xkb/xkb_keyboard_layout_engine_unittest.cc",
     ]
     deps += [
       "//ui/events/ozone:events_ozone",
       "//ui/events/ozone:events_ozone_evdev",
       "//ui/events/ozone:events_ozone_layout",
     ]
   }
 
   if (use_aura) {
-    sources += [ "gestures/gesture_provider_aura_unittest.cc" ]
+    sources += [
+      "gestures/gesture_provider_aura_unittest.cc",
+      "gestures/motion_event_aura_unittest.cc",
+    ]
   }
 }