Remove xfa/src/fwl/src and move code up a level.

xfa/src/fwl/lightwidget/theme.cpp

 // Copyright 2014 PDFium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 // Original code copyright 2014 Foxit Software Inc. http://www.foxitsoftware.com
 
 #include "xfa/include/fwl/lightwidget/theme.h"
 
 #include <algorithm>
 
@@ skipping 115 matching lines @@
   return FWL_ERR_Succeeded;
 }
 
 CFWL_WidgetTP* CFWL_Theme::GetTheme(IFWL_Widget* pWidget) {
   for (const auto& pTheme : m_ThemesArray) {
     if (pTheme->IsValidWidget(pWidget))
       return pTheme.get();
   }
   return nullptr;
 }