Avoid the ptr.reset(new XXX()) anti-pattern

xfa/fxfa/app/xfa_ffdocview.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/xfa_ffdocview.h"
 
 #include "core/fxcrt/fx_ext.h"
+#include "third_party/base/ptr_util.h"
 #include "third_party/base/stl_util.h"
 #include "xfa/fxfa/app/xfa_ffbarcode.h"
 #include "xfa/fxfa/app/xfa_ffcheckbutton.h"
 #include "xfa/fxfa/app/xfa_ffchoicelist.h"
 #include "xfa/fxfa/app/xfa_ffdraw.h"
 #include "xfa/fxfa/app/xfa_ffexclgroup.h"
 #include "xfa/fxfa/app/xfa_fffield.h"
 #include "xfa/fxfa/app/xfa_ffimage.h"
 #include "xfa/fxfa/app/xfa_ffimageedit.h"
 #include "xfa/fxfa/app/xfa_ffpath.h"
@@ skipping 286 matching lines @@
     if (!pRootItem) {
       return XFA_EVENTERROR_Error;
     }
     pNode = pRootItem->GetChild(0, XFA_Element::Subform);
   }
   ExecEventActivityByDeepFirst(pNode, pParam->m_eType, pParam->m_bIsFormReady,
                                true, nullptr);
   return XFA_EVENTERROR_Success;
 }
 CXFA_FFWidgetHandler* CXFA_FFDocView::GetWidgetHandler() {
-  if (!m_pWidgetHandler) {
-    m_pWidgetHandler.reset(new CXFA_FFWidgetHandler(this));
-  }
+  if (!m_pWidgetHandler)
+    m_pWidgetHandler = pdfium::MakeUnique<CXFA_FFWidgetHandler>(this);
+
   return m_pWidgetHandler.get();
 }
 
 CXFA_WidgetAccIterator* CXFA_FFDocView::CreateWidgetAccIterator(
     XFA_WIDGETORDER eOrder) {
   CXFA_Node* pFormRoot = GetRootSubform();
   return pFormRoot ? new CXFA_WidgetAccIterator(this, pFormRoot) : nullptr;
 }
 CXFA_FFWidget* CXFA_FFDocView::GetFocusWidget() {
   return m_pFocusWidget;
@@ skipping 522 matching lines @@
 }
 
 bool CXFA_WidgetAccIterator::SetCurrentWidgetAcc(CXFA_WidgetAcc* hWidget) {
   return false;
 }
 
 void CXFA_WidgetAccIterator::SkipTree() {
   m_ContentIterator.SkipChildrenAndMoveToNext();
   m_pCurWidgetAcc = nullptr;
 }