+ set object name to tool buttons with popup menu

src/Gui/Action.cpp

@@ -234,6 +234,7 @@ void ActionGroup::addTo(QWidget *w)
             w->addAction(_action);
             QToolButton* tb = w->findChildren<QToolButton*>().last();
             tb->setPopupMode(QToolButton::MenuButtonPopup);
+            tb->setObjectName(QString::fromLatin1("qt_toolbutton_menubutton"));
             QList<QAction*> acts = _group->actions();
             QMenu* menu = new QMenu(tb);
             menu->addActions(acts);

src/Gui/DlgToolbarsImp.cpp

@@ -724,6 +724,7 @@ void DlgCustomToolbarsImp::setActionGroup(QAction* action, const QList<QAction*>
             QMenu* menu = tb->menu();
             if (!menu) {
                 tb->setPopupMode(QToolButton::MenuButtonPopup);
+                tb->setObjectName(QString::fromLatin1("qt_toolbutton_menubutton"));
                 QMenu* menu = new QMenu(tb);
                 menu->addActions(group);
                 tb->setMenu(menu);