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

xfa/fxfa/app/xfa_ffpushbutton.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/fxfa/app/xfa_ffpushbutton.h"
 
 #include "xfa/fwl/core/cfwl_widgetmgr.h"
 #include "xfa/fwl/core/fwl_noteimp.h"
@@ skipping 41 matching lines @@
                                                  pGS, &mt);
 }
 FX_BOOL CXFA_FFPushButton::LoadWidget() {
   ASSERT(!m_pNormalWidget);
   CFWL_PushButton* pPushButton = CFWL_PushButton::Create();
   if (pPushButton) {
     pPushButton->Initialize();
   }
   m_pOldDelegate = pPushButton->SetDelegate(this);
   m_pNormalWidget = (CFWL_Widget*)pPushButton;
+  m_pNormalWidget->SetLayoutItem(this);
   IFWL_Widget* pWidget = m_pNormalWidget->GetWidget();
-  m_pNormalWidget->SetPrivateData(pWidget, this, NULL);
   CFWL_NoteDriver* pNoteDriver = FWL_GetApp()->GetNoteDriver();
   pNoteDriver->RegisterEventTarget(pWidget, pWidget);
   m_pNormalWidget->LockUpdate();
   UpdateWidgetProperty();
   LoadHighlightCaption();
   m_pNormalWidget->UnlockUpdate();
   return CXFA_FFField::LoadWidget();
 }
 void CXFA_FFPushButton::UpdateWidgetProperty() {
   uint32_t dwStyleEx = 0;
@@ skipping 164 matching lines @@
       pGraphics->SetLineWidth(fLineWidth);
       CFX_Path path;
       path.Create();
       CFX_RectF rect;
       m_pNormalWidget->GetWidgetRect(rect);
       path.AddRectangle(0, 0, rect.width, rect.height);
       pGraphics->StrokePath(&path, (CFX_Matrix*)pMatrix);
     }
   }
 }