QmlProfiler: read trace when application ended by the user

This patch avoids showing the "use the stop button" if the
application dies but the trace data was sent in time.

Note: with the current implementation in Qt5, the application
sometimes closes before all data could be sent.  That happens
with any non-trivial qml application.

Change-Id: Ie7b1568b2d69320d1887587dccac40a4b4d4d788
Reviewed-by: Aurindam Jana <aurindam.jana@nokia.com>