slot: fix name of method not used by ui anymore

Qt auto-link this method with their name and so complain
since their not linked anymore

Regression introduced by 3338

Change-Id: Ib1ba23dc7b58cbb061b31671fd8caba3d68b0fa5
Tuleap: #148
diff --git a/mainwindow.cpp b/mainwindow.cpp
index 05e3384..cc9b732 100644
--- a/mainwindow.cpp
+++ b/mainwindow.cpp
@@ -86,11 +86,11 @@
     auto callWidget = static_cast<CallWidget*>(navStack_->getNavWidget(ScreenEnum::CallScreen));
 
     connect(mwToolBar_->getSettingsButton(), &QAction::triggered,
-            callWidget, &CallWidget::on_settingsButton_clicked);
+            callWidget, &CallWidget::settingsButton_clicked);
     connect(mwToolBar_->getHistoryButton(), &QAction::triggered,
-            callWidget, &CallWidget::on_historicButton_clicked);
+            callWidget, &CallWidget::historicButton_clicked);
     connect(mwToolBar_->getContactListButton(), &QAction::triggered,
-            callWidget, &CallWidget::on_contactButton_clicked);
+            callWidget, &CallWidget::contactButton_clicked);
 
 #ifdef ENABLE_AUTOUPDATE
     win_sparkle_set_appcast_url("http://gpl.savoirfairelinux.net/ring-download/windows/winsparkle-ring.xml");