Make sure it is always emitted if the parseInProgress state changes

Change-Id: I0e8dc6df5c68f14bd51885c078e909be10af8efa
Task-Nr: QTCREATORBUG-6057
Reviewed-on: http://codereview.qt-project.org/4657


Reviewed-by: Qt Sanity Bot <qt_sanity_bot@ovi.com>
Reviewed-by: Daniel Teske <daniel.teske@nokia.com>
Reviewed-by: Christian Kandeler <christian.kandeler@nokia.com>