Implement proper wxCursor cloning in wxDFB.

wxDFB compilation was broken by recent wxObjectRefData copy ctor-related
changes. Fix it by not using wxCursorRefData copy ctor any more, call
wxCursorRefData::Clone() which does the right thing explicitly instead.

Closes #12791.

git-svn-id: https://svn.wxwidgets.org/svn/wx/wxWidgets/trunk@66429 c3d73ce0-8a6f-49c7-b76d-6d57e0e08775

src/dfb/cursor.cpp

@@ -30,6 +30,15 @@ public:
 
     virtual bool IsOk() const { return m_bitmap.IsOk(); }
 
+    // Create a deep copy of this object.
+    wxCursorRefData *Clone() const
+    {
+        wxBitmap bitmapCopy(m_bitmap);
+        bitmapCopy.UnShare();
+
+        return new wxCursorRefData(bitmapCopy, m_id);
+    }
+
     int      m_id;
     wxBitmap m_bitmap;
 };
@@ -62,7 +71,7 @@ wxGDIRefData *wxCursor::CreateGDIRefData() const
 
 wxGDIRefData *wxCursor::CloneGDIRefData(const wxGDIRefData *data) const
 {
-    return new wxCursorRefData(*(wxCursorRefData *)data);
+    return static_cast<const wxCursorRefData *>(data)->Clone();
 }