Add ptr_util.h from base until std::make_unique<> available

core/fxge/dib/fx_dib_engine.cpp

Index: core/fxge/dib/fx_dib_engine.cpp
diff --git a/core/fxge/dib/fx_dib_engine.cpp b/core/fxge/dib/fx_dib_engine.cpp
index c8e955888886a9282ac9218f612261d71bfcab24..389cf239098f5a467dc20d5baabb255acf495b9b 100644
--- a/core/fxge/dib/fx_dib_engine.cpp
+++ b/core/fxge/dib/fx_dib_engine.cpp
@@ -10,6 +10,7 @@
 
 #include "core/fxge/dib/dib_int.h"
 #include "core/fxge/fx_dib.h"
+#include "third_party/base/ptr_util.h"
 
 namespace {
 
@@ -930,9 +931,9 @@ FX_BOOL CFX_ImageStretcher::Continue(IFX_Pause* pPause) {
 }
 
 FX_BOOL CFX_ImageStretcher::StartStretch() {
-  m_pStretchEngine = WrapUnique(
-      new CStretchEngine(m_pDest, m_DestFormat, m_DestWidth, m_DestHeight,
-                         m_ClipRect, m_pSource, m_Flags));
+  m_pStretchEngine = pdfium::MakeUnique<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);