Make sure that all loaded xrc dialogs have the correct parent

This might be overkill, but shouldn't hurt.

src/wx/guiinit.cpp

@@ -2082,6 +2082,13 @@ wxDialog * MainFrame::LoadXRCDialog(const char * name)
     wxString dname = wxString::FromUTF8(name);
     wxDialog * dialog = wxXmlResource::Get()->LoadDialog(this, dname);
     CheckThrowXRCError(dialog,name);
+
+    /* wx-2.9.1 doesn't set parent for propertysheetdialogs for some reason */
+    /* this will generate a gtk warning but it is necessary for later */
+    /* retrieval using FindWindow() */
+    if(!dialog->GetParent())
+        dialog->Reparent(this);
+    mark_recursive(dialog);
     return dialog;
 }
 wxPropertySheetDialog * MainFrame::LoadXRCropertySheetDialog(const char * name)