Editors: Provide a base implementation for {save,restore}State

Change-Id: Iedfc0d59ecfe257ad5823cff39977bce82ada3a5
Reviewed-by: Eike Ziller <eike.ziller@digia.com>

src/plugins/diffeditor/diffeditoreditable.cpp

@@ -225,15 +225,4 @@ void DiffEditorEditable::activateEntry(int index)
     updateEntryToolTip();
 }
 
-QByteArray DiffEditorEditable::saveState() const
-{
-    return QByteArray();
-}
-
-bool DiffEditorEditable::restoreState(const QByteArray &state)
-{
-    Q_UNUSED(state)
-    return true;
-}
-
 } // namespace DiffEditor