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

xfa/fwl/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/cfwl_widgetmgr.h"
 
 #include <utility>
 
@@ skipping 545 matching lines @@
 }
 
 CFX_Graphics* CFWL_WidgetMgr::DrawWidgetBefore(CFWL_Widget* pWidget,
                                                CFX_Graphics* pGraphics,
                                                const CFX_Matrix* pMatrix) {
   if (!FWL_UseOffscreen(pWidget))
     return pGraphics;
 
   Item* pItem = GetWidgetMgrItem(pWidget);
   if (!pItem->pOffscreen) {
-    pItem->pOffscreen.reset(new CFX_Graphics);
+    pItem->pOffscreen = pdfium::MakeUnique<CFX_Graphics>();
     CFX_RectF rect = pWidget->GetWidgetRect();
     pItem->pOffscreen->Create((int32_t)rect.width, (int32_t)rect.height,
                               FXDIB_Argb);
   }
   CFX_RectF rect;
   pGraphics->GetClipRect(rect);
   pItem->pOffscreen->SetClipRect(rect);
   return pItem->pOffscreen.get();
 }
 
@@ skipping 142 matching lines @@
       pWidget(widget),
       iRedrawCounter(0)
 #if (_FX_OS_ == _FX_WIN32_DESKTOP_) || (_FX_OS_ == _FX_WIN64_)
       ,
       bOutsideChanged(false)
 #endif
 {
 }
 
 CFWL_WidgetMgr::Item::~Item() {}