Add borders if none specified

git-svn-id: https://svn.wxwidgets.org/svn/wx/wxWidgets/trunk@70685 c3d73ce0-8a6f-49c7-b76d-6d57e0e08775

src/osx/listbox_osx.cpp

@@ -74,6 +74,9 @@ bool wxListBox::Create(
     DontCreatePeer();
     m_blockEvents = false;
 
+    if ( ! (style & wxNO_BORDER) )
+        style = (style & ~wxBORDER_MASK) | wxSUNKEN_BORDER ;
+
     wxASSERT_MSG( !(style & wxLB_MULTIPLE) || !(style & wxLB_EXTENDED),
                   wxT("only a single listbox selection mode can be specified") );