Private slots should be named starting with _q_

Private slots should be named starting with _q_

This is to reduce the risk of collisions with signals/slots in user classes

 q_updateFocusObject(QObject *object) => _q_updateFocusObject(QObject *object)
 q_checkFocusObject(QObject *object)  => _q_checkFocusObject(QObject *object)
 q_connectFocusObject()               => _q_connectFocusObject()
 emitActivated(QPlatformSystemTrayIcon::ActivationReason) => _q_emitActivated(QPlatformSystemTrayIcon::ActivationReason)

Change-Id: I148913f1e24a80fe5cacfd737d1b455b805cfced
Reviewed-by: Christoph Schleifenbaum <christoph.schleifenbaum@kdab.com>
Reviewed-by: Rohan McGovern <rohan.mcgovern@nokia.com>