Linux Aura: Use system title bar is now set by preference, not flag.

chrome/browser/ui/browser_view_prefs.cc

 // Copyright (c) 2012 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 "chrome/browser/ui/browser_view_prefs.h"
 
 #include "base/prefs/pref_registry_simple.h"
 #include "chrome/common/pref_names.h"
+#include "components/user_prefs/pref_registry_syncable.h"
 
 namespace {
 
 // How long do we wait before we consider a window hung (in ms).
 const int kDefaultPluginMessageResponseTimeout = 25000;
 
 // How frequently we check for hung plugin windows.
 const int kDefaultHungPluginDetectFrequency = 2000;
 
 }  // namespace
 
 namespace chrome {
 
 void RegisterBrowserViewPrefs(PrefRegistrySimple* registry) {
   registry->RegisterIntegerPref(prefs::kPluginMessageResponseTimeout,
                                 kDefaultPluginMessageResponseTimeout);
   registry->RegisterIntegerPref(prefs::kHungPluginDetectFrequency,
                                 kDefaultHungPluginDetectFrequency);
 }
 
+void RegisterBrowserViewSyncablePrefs(
+    user_prefs::PrefRegistrySyncable* registry) {
+  // TODO(mgiuca): Decide on this default depending on the window manager. See
+  // BrowserWindowGtk::GetCustomFramePrefDefault.
+  bool custom_frame_default = true;
+
+  registry->RegisterBooleanPref(
+      prefs::kUseCustomChromeFrame,
+      custom_frame_default,
+      user_prefs::PrefRegistrySyncable::UNSYNCABLE_PREF);
+}
+
 }  // namespace chrome