aura: Explicitly disable GTK

base/message_loop.cc

 // Copyright (c) 2011 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.
 
 #include "base/message_loop.h"
 
 #include <algorithm>
 
 #include "base/bind.h"
 #include "base/compiler_specific.h"
@@ skipping 11 matching lines @@
 
 #if defined(OS_MACOSX)
 #include "base/message_pump_mac.h"
 #endif
 #if defined(OS_POSIX)
 #include "base/message_pump_libevent.h"
 #endif
 #if defined(OS_ANDROID)
 #include "base/message_pump_android.h"
 #endif
-#if defined(OS_POSIX) && !defined(OS_MACOSX) && !defined(OS_ANDROID)
+#if defined(TOOLKIT_USES_GTK)
 #include <gdk/gdk.h>
 #include <gdk/gdkx.h>
 #endif  // defined(OS_POSIX) && !defined(OS_MACOSX)
 
 using base::TimeDelta;
 using base::TimeTicks;
 
 namespace {
 
 // A lazily created thread local storage for quick access to a thread's message
@@ skipping 803 matching lines @@
                                            Watcher *delegate) {
   return pump_libevent()->WatchFileDescriptor(
       fd,
       persistent,
       static_cast<base::MessagePumpLibevent::Mode>(mode),
       controller,
       delegate);
 }
 
 #endif