Change IFWL_Widget to store a single delegate.

xfa/fwl/core/cfwl_widgetmgr.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/fwl/core/cfwl_widgetmgr.h"
 
 #include "xfa/fwl/core/cfwl_message.h"
 #include "xfa/fwl/core/fwl_noteimp.h"
@@ skipping 595 matching lines @@
   pWidget->GetWidgetRect(clipCopy);
   clipCopy.left = clipCopy.top = 0;
   if (bUseOffscreenDirect(pWidget)) {
     DrawWidgetAfter(pWidget, pGraphics, clipCopy, pMatrix);
     return;
   }
   CFX_RectF clipBounds;
 
 #if _FX_OS_ == _FX_WIN32_DESKTOP_ || _FX_OS_ == _FX_WIN64_ || \
     _FX_OS_ == _FX_LINUX_DESKTOP_ || _FX_OS_ == _FX_ANDROID_
-  pWidget->GetCurrentDelegate()->OnDrawWidget(pTemp, pMatrix);
+  pWidget->GetDelegate()->OnDrawWidget(pTemp, pMatrix);
   pGraphics->GetClipRect(clipBounds);
   clipCopy = clipBounds;
 #elif _FX_OS_ == _FX_MACOSX_
   if (m_pWidgetMgr->IsFormDisabled()) {
     pWidget->GetCurrentDelegate()->OnDrawWidget(pTemp, pMatrix);
     pGraphics->GetClipRect(clipBounds);
     clipCopy = clipBounds;
   } else {
     clipBounds.Set(pMatrix->a, pMatrix->b, pMatrix->c, pMatrix->d);
     const_cast<CFX_Matrix*>(pMatrix)->SetIdentity();  // FIXME: const cast.
@@ skipping 44 matching lines @@
       widgetMatrix.TransformPoint(clipBounds.left, clipBounds.top);
       clipBounds.Intersect(rtClip);
       if (clipBounds.IsEmpty())
         continue;
 
       pGraphics->SaveGraphState();
       pGraphics->SetClipRect(clipBounds);
     }
     widgetMatrix.Translate(rtWidget.left, rtWidget.top, TRUE);
 
-    if (IFWL_WidgetDelegate* pDelegate = child->GetCurrentDelegate()) {
+    if (IFWL_WidgetDelegate* pDelegate = child->GetDelegate()) {
       if (m_pWidgetMgr->IsFormDisabled() ||
           IsNeedRepaint(child, &widgetMatrix, rtClip)) {
         pDelegate->OnDrawWidget(pGraphics, &widgetMatrix);
       }
     }
     if (!bFormDisable)
       pGraphics->RestoreGraphState();
 
     DrawChild(child, clipBounds, pGraphics,
               bFormDisable ? &widgetMatrix : pMatrix);
@@ skipping 169 matching lines @@
       pWidget(widget),
       iRedrawCounter(0)
 #if (_FX_OS_ == _FX_WIN32_DESKTOP_) || (_FX_OS_ == _FX_WIN64_)
       ,
       bOutsideChanged(FALSE)
 #endif
 {
 }
 
 CFWL_WidgetMgrItem::~CFWL_WidgetMgrItem() {}