GN: Get os="chromeos" use_ozone=true to compile

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")
 
 static_library("dom4_keycode_converter") {
   sources = [
     "keycodes/dom4/keycode_converter.cc",
     "keycodes/dom4/keycode_converter.h",
@@ skipping 305 matching lines @@
       "devices/x11/device_data_manager_x11_unittest.cc",
       "x/events_x_unittest.cc",
     ]
   }
 
   if (use_ozone) {
     sources += [
       "ozone/evdev/event_converter_evdev_impl_unittest.cc",
       "ozone/evdev/touch_event_converter_evdev_unittest.cc",
     ]
+    deps += [
+      "//ui/events/ozone:events_ozone",
+      "//ui/events/ozone:events_ozone_evdev",
+    ]
   }
 
   if (use_aura) {
     sources += [
       "gestures/gesture_provider_aura_unittest.cc",
     ]
   }
 }