Handle PPK_CustomBase in QWin32PrintEngine::property

If we leave out the default so that the compiler catches missing enum
values we should actually handle them all ...

Change-Id: Ieb4992dec84ce847e48ab3c4a94bd8825a148706
Reviewed-by: Andy Shaw <andy.shaw@digia.com>

src/printsupport/kernel/qprintengine_win.cpp

@@ -1414,6 +1414,9 @@ QVariant QWin32PrintEngine::property(PrintEnginePropertyKey key) const
         value.setValue(d->m_pageLayout);
         break;
 
+    case PPK_CustomBase:
+        break;
+
     // No default so that compiler will complain if new keys added and not handled in this engine
     }
     return value;