mandoline: write this after lunch.

components/mus/example/views_examples/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("//mojo/public/mojo_application.gni")
 import("//mojo/public/tools/bindings/mojom.gni")
 import("//tools/grit/repack.gni")
 
 mojo_native_application("views_examples") {
   testonly = true
 
   sources = [
     "main.cc",
     "views_examples_application_delegate.cc",
     "views_examples_application_delegate.h",
   ]
 
   deps = [
     "//base",
     "//components/mus/public/interfaces",
     "//mojo/application/public/cpp",
     "//mojo/application/public/cpp:sources",
     "//mojo/converters/geometry",
     "//mojo/public/cpp/bindings",
+    "//mojo/services/tracing/public/cpp",
     "//skia",
     "//ui/gfx",
     "//ui/gfx/geometry",
     "//ui/views",
     "//ui/views/examples:views_examples_lib",
     "//ui/views/mus:for_mojo_application",
   ]
 
   resources = [ "$root_out_dir/views_mus_resources.pak" ]
 
   data_deps = [
     "//components/mus",
   ]
 }