Improved stability of tst_qstatemachine, mark as parallel-safe

tst_QStateMachine::postEventFromOtherThread() assumed that 10,000
iterations of the event loop in a separate thread could always be
completed successfully within the default QTRY_COMPARE timeout.
This may be false if the CPU load is already high - such as when running
other tests concurrently.

Decrease the iteration count.

Change-Id: I780523f73c0c16fa0b2ab3201b2b0affdebc198d
Reviewed-by: Toby Tomkins <toby.tomkins@nokia.com>
Reviewed-by: Kalle Lehtonen <kalle.ju.lehtonen@nokia.com>

tests/auto/corelib/statemachine/qstatemachine/qstatemachine.pro

@@ -1,4 +1,5 @@
 CONFIG += testcase
+CONFIG += parallel_test
 TARGET = tst_qstatemachine
 QT = core-private testlib gui widgets
 SOURCES = tst_qstatemachine.cpp

tests/auto/corelib/statemachine/qstatemachine/tst_qstatemachine.cpp

@@ -3753,7 +3753,7 @@ private Q_SLOTS:
     void postEvent()
     {
         m_machine->postEvent(new QEvent(QEvent::User));
-        if (++m_count < 10000)
+        if (++m_count < 1000)
             QTimer::singleShot(0, this, SLOT(postEvent()));
         else
             quit();