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

chrome/browser/ui/views/frame/browser_view.cc

 // Copyright 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/views/frame/browser_view.h"
 
 #include <stdint.h>
 
 #include <algorithm>
 #include <memory>
@@ skipping 1890 matching lines @@
 }
 
 void BrowserView::OnThemeChanged() {
   if (!IsRegularOrGuestSession()) {
     // When the theme changes, the native theme may also change (in incognito,
     // the usage of dark or normal hinges on the browser theme), so we have to
     // propagate both kinds of change.
     base::AutoReset<bool> reset(&handling_theme_changed_, true);
 #if defined(OS_WIN)
     ui::NativeThemeDarkWin::instance()->NotifyObservers();
-    ui::NativeThemeWin::instance()->NotifyObservers();
 #elif defined(OS_LINUX)
     ui::NativeThemeDarkAura::instance()->NotifyObservers();
-    ui::NativeThemeAura::instance()->NotifyObservers();
 #endif
+    ui::NativeTheme::GetInstanceForNativeUi()->NotifyObservers();
   }
 
   views::View::OnThemeChanged();
 }
 
 void BrowserView::OnNativeThemeChanged(const ui::NativeTheme* theme) {
   // Do not handle native theme changes before the browser view is initialized.
   if (!initialized_)
     return;
   ClientView::OnNativeThemeChanged(theme);
@@ skipping 663 matching lines @@
 }
 
 extensions::ActiveTabPermissionGranter*
 BrowserView::GetActiveTabPermissionGranter() {
   content::WebContents* web_contents = GetActiveWebContents();
   if (!web_contents)
     return nullptr;
   return extensions::TabHelper::FromWebContents(web_contents)
       ->active_tab_permission_granter();
 }