Replace a few more std::unique_ptr.reset() with WrapUnique assignments.

core/fxge/dib/fx_dib_engine.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 <limits.h>
 
 #include <algorithm>
 
@@ skipping 912 matching lines @@
   return StartStretch();
 }
 
 FX_BOOL CFX_ImageStretcher::Continue(IFX_Pause* pPause) {
   if (m_Flags & FXDIB_DOWNSAMPLE)
     return ContinueQuickStretch(pPause);
   return ContinueStretch(pPause);
 }
 
 FX_BOOL CFX_ImageStretcher::StartStretch() {
-  m_pStretchEngine.reset(new CStretchEngine(m_pDest, m_DestFormat, m_DestWidth,
-                                            m_DestHeight, m_ClipRect, m_pSource,
-                                            m_Flags));
+  m_pStretchEngine = WrapUnique(
+      new CStretchEngine(m_pDest, m_DestFormat, m_DestWidth, m_DestHeight,
+                         m_ClipRect, m_pSource, m_Flags));
   m_pStretchEngine->StartStretchHorz();
   if (SourceSizeWithinLimit(m_pSource->GetWidth(), m_pSource->GetHeight())) {
     m_pStretchEngine->Continue(nullptr);
     return FALSE;
   }
   return TRUE;
 }
 
 FX_BOOL CFX_ImageStretcher::ContinueStretch(IFX_Pause* pPause) {
   return m_pStretchEngine && m_pStretchEngine->Continue(pPause);
@@ skipping 52 matching lines @@
                                   result_width);
     if (m_pMaskScanline) {
       m_pSource->m_pAlphaMask->DownSampleScanline(
           src_y, m_pMaskScanline.get(), 1, m_DestWidth, m_bFlipX,
           m_ClipRect.left, result_width);
     }
     m_pDest->ComposeScanline(dest_y, m_pScanline.get(), m_pMaskScanline.get());
   }
   return FALSE;
 }