Return unique_ptrs from CFX_DIBitmap::Clone().

core/fxge/dib/fx_dib_convert.cpp

Index: core/fxge/dib/fx_dib_convert.cpp
diff --git a/core/fxge/dib/fx_dib_convert.cpp b/core/fxge/dib/fx_dib_convert.cpp
index f5ae563d57e6444fcfc61051936f9a87c92c5b12..e4c65f35d66a7d4c02a3f6c745925bf74d09bc25 100644
--- a/core/fxge/dib/fx_dib_convert.cpp
+++ b/core/fxge/dib/fx_dib_convert.cpp
@@ -781,7 +781,8 @@ bool ConvertBuffer(FXDIB_Format dest_format,
   }
 }
 
-CFX_DIBitmap* CFX_DIBSource::CloneConvert(FXDIB_Format dest_format) const {
+std::unique_ptr<CFX_DIBitmap> CFX_DIBSource::CloneConvert(
+    FXDIB_Format dest_format) const {
   if (dest_format == GetFormat())
     return Clone(nullptr);
 
@@ -819,7 +820,8 @@ CFX_DIBitmap* CFX_DIBSource::CloneConvert(FXDIB_Format dest_format) const {
   }
   if (pal_8bpp)
     pClone->CopyPalette(pal_8bpp.get());
-  return pClone.release();
+
+  return pClone;
 }
 
 bool CFX_DIBitmap::ConvertFormat(FXDIB_Format dest_format) {