Make gn check //mojo/public/* pass

mojo/public/cpp/utility/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.
 
 source_set("utility") {
   sources = [
     "mutex.h",
     "run_loop.h",
     "run_loop_handler.h",
     "thread.h",
     "lib/mutex.cc",
     "lib/run_loop.cc",
     "lib/thread.cc",
     "lib/thread_local.h",
     "lib/thread_local_posix.cc",
     "lib/thread_local_win.cc",
   ]
 
+  deps = [
+    "//mojo/public/cpp/bindings:callback",
+    "//mojo/public/cpp/system",
+  ]
+
   if (is_win) {
     # See crbug.com/342893:
     sources -= [
       "mutex.h",
       "thread.h",
       "lib/mutex.cc",
       "lib/thread.cc",
     ]
   }
 }