Try to get rid of all direct references to particular native themes.

ui/views/widget/desktop_aura/desktop_window_tree_host_x11.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 "ui/views/widget/desktop_aura/desktop_window_tree_host_x11.h"
 
 #include <X11/extensions/shape.h>
 #include <X11/extensions/XInput2.h>
 #include <X11/Xatom.h>
 #include <X11/Xregion.h>
@@ skipping 31 matching lines @@
 #include "ui/events/null_event_targeter.h"
 #include "ui/events/platform/platform_event_source.h"
 #include "ui/events/platform/x11/x11_event_source.h"
 #include "ui/gfx/geometry/insets.h"
 #include "ui/gfx/geometry/size_conversions.h"
 #include "ui/gfx/image/image_skia.h"
 #include "ui/gfx/image/image_skia_rep.h"
 #include "ui/gfx/path.h"
 #include "ui/gfx/path_x11.h"
 #include "ui/native_theme/native_theme.h"
-#include "ui/native_theme/native_theme_aura.h"
 #include "ui/views/corewm/tooltip_aura.h"
 #include "ui/views/linux_ui/linux_ui.h"
 #include "ui/views/views_delegate.h"
 #include "ui/views/views_switches.h"
 #include "ui/views/widget/desktop_aura/desktop_drag_drop_client_aurax11.h"
 #include "ui/views/widget/desktop_aura/desktop_native_cursor_manager.h"
 #include "ui/views/widget/desktop_aura/desktop_native_widget_aura.h"
 #include "ui/views/widget/desktop_aura/desktop_window_tree_host_observer_x11.h"
 #include "ui/views/widget/desktop_aura/x11_desktop_handler.h"
 #include "ui/views/widget/desktop_aura/x11_desktop_window_move_client.h"
@@ skipping 2275 matching lines @@
 
 // static
 ui::NativeTheme* DesktopWindowTreeHost::GetNativeTheme(aura::Window* window) {
   const LinuxUI* linux_ui = LinuxUI::instance();
   if (linux_ui) {
     ui::NativeTheme* native_theme = linux_ui->GetNativeTheme(window);
     if (native_theme)
       return native_theme;
   }
 
-  return ui::NativeThemeAura::instance();
+  return ui::NativeTheme::GetInstanceForNativeUi();
 }
 
 }  // namespace views