QmlProfiler: Refactor complete() methods

The complete() methods do something more specific. We should call them
by what they do. Also, we don't need to signal the finishing of data
acquisition via a signal and most of the postprocessing can happen in
the worker thread.

Change-Id: Iae986aefb8e7e7d4327c481d7a85325bbff7fa48
Reviewed-by: Joerg Bornemann <joerg.bornemann@theqtcompany.com>

src/plugins/qmlprofiler/qmlprofilerclientmanager.h

@@ -62,7 +62,6 @@ public:
 signals:
     void connectionFailed();
     void connectionClosed();
-    void dataReadyForProcessing();
 
 public slots:
     void connectClient(quint16 port);