added wxAppTraits::CreateRenderer() which may be used to customize the renderer

git-svn-id: https://svn.wxwidgets.org/svn/wx/wxWidgets/trunk@22341 c3d73ce0-8a6f-49c7-b76d-6d57e0e08775

src/common/appcmn.cpp

@@ -322,6 +322,12 @@ wxFontMapper *wxGUIAppTraitsBase::CreateFontMapper()
 
 #endif // wxUSE_FONTMAP
 
+wxRendererNative *wxGUIAppTraitsBase::CreateRenderer()
+{
+    // use the default native renderer by default
+    return NULL;
+}
+
 #ifdef __WXDEBUG__
 
 bool wxGUIAppTraitsBase::ShowAssertDialog(const wxString& msg)