Replace more static casts in FWL (part 3)

xfa/include/fwl/core/fwl_widgetmgr.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 _FWL_WIDGETMGR_H
 #define _FWL_WIDGETMGR_H
 class IFWL_Widget;
 class IFWL_WidgetMgr;
@@ skipping 12 matching lines @@
 class IFWL_WidgetMgr {
  public:
   virtual ~IFWL_WidgetMgr() {}
   virtual int32_t CountWidgets(IFWL_Widget* pParent = NULL) = 0;
   virtual IFWL_Widget* GetWidget(int32_t nIndex,
                                  IFWL_Widget* pParent = NULL) = 0;
   virtual IFWL_Widget* GetWidget(IFWL_Widget* pWidget,
                                  FWL_WGTRELATION eRelation) = 0;
   virtual int32_t GetWidgetIndex(IFWL_Widget* pWidget) = 0;
   virtual FX_BOOL SetWidgetIndex(IFWL_Widget* pWidget, int32_t nIndex) = 0;
-  virtual FX_BOOL IsWidget(void* pObj) = 0;
   virtual FWL_ERR RepaintWidget(IFWL_Widget* pWidget,
                                 const CFX_RectF* pRect = NULL) = 0;
   virtual FX_DWORD GetCapability() = 0;
 };
 IFWL_WidgetMgr* FWL_GetWidgetMgr();
 FX_BOOL FWL_WidgetIsChild(IFWL_Widget* parent, IFWL_Widget* find);
 #define FWL_WGTMGR_DisableThread 0x00000001
 #define FWL_WGTMGR_DisableForm 0x00000002
 class IFWL_WidgetMgrDelegate {
  public:
   virtual ~IFWL_WidgetMgrDelegate() {}
   virtual FWL_ERR OnSetCapability(
       FX_DWORD dwCapability = FWL_WGTMGR_DisableThread) = 0;
   virtual int32_t OnProcessMessageToForm(CFWL_Message* pMessage) = 0;
   virtual FWL_ERR OnDrawWidget(IFWL_Widget* pWidget,
                                CFX_Graphics* pGraphics,
                                const CFX_Matrix* pMatrix = NULL) = 0;
 };
 FWL_ERR FWL_WidgetMgrSnapshot(IFWL_Widget* pWidget,
                               const CFX_WideString* saveFile,
                               const CFX_Matrix* pMatrix = NULL);
 #endif