Add opaque "layout item" to widgets for caller's use.

xfa/fwl/lightwidget/cfwl_widget.h

 // 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
 
 #ifndef XFA_FWL_LIGHTWIDGET_CFWL_WIDGET_H_
 #define XFA_FWL_LIGHTWIDGET_CFWL_WIDGET_H_
 
 #include "xfa/fwl/core/cfwl_event.h"
@@ skipping 23 matching lines @@
   FWL_Error SetParent(CFWL_Widget* pParent);
   CFWL_Widget* GetOwner();
   FWL_Error SetOwner(CFWL_Widget* pOwner);
   uint32_t GetStyles();
   FWL_Error ModifyStyles(uint32_t dwStylesAdded, uint32_t dwStylesRemoved);
   uint32_t GetStylesEx();
   FWL_Error ModifyStylesEx(uint32_t dwStylesExAdded,
                            uint32_t dwStylesExRemoved);
   uint32_t GetStates();
   void SetStates(uint32_t dwStates, FX_BOOL bSet = TRUE);
+  void* GetLayoutItem() const;
+  void SetLayoutItem(void* pItem);
+
   FWL_Error SetPrivateData(void* module_id,
                            void* pData,
                            PD_CALLBACK_FREEDATA callback);
   void* GetPrivateData(void* module_id);
   FWL_Error Update();
   FWL_Error LockUpdate();
   FWL_Error UnlockUpdate();
   FWL_WidgetHit HitTest(FX_FLOAT fx, FX_FLOAT fy);
   FWL_Error TransformTo(CFWL_Widget* pWidget, FX_FLOAT& fx, FX_FLOAT& fy);
   FWL_Error TransformTo(CFWL_Widget* pWidget, CFX_RectF& rt);
@@ skipping 16 matching lines @@
   IFWL_Widget* m_pIface;
   IFWL_WidgetDelegate* m_pDelegate;
   CFWL_WidgetMgr* m_pWidgetMgr;
   CFWL_WidgetProperties* m_pProperties;
 
  protected:
   FWL_Error Initialize(const CFWL_WidgetProperties* pProperties = NULL);
 };
 
 #endif  // XFA_FWL_LIGHTWIDGET_CFWL_WIDGET_H_