Qml Tooling: Test that trace events arrive in chronological order

The QML profiler trace client should resolve any deviations from
chronological order. Trace receivers should not need to deal with this.

Change-Id: I9bbb387bbb5c0b7da9f2b508d228665af9f27d4c
Reviewed-by: Michael Brasser <michael.brasser@live.com>

tests/auto/qml/debugger/qqmlprofilerservice/tst_qqmlprofilerservice.cpp

@@ -69,6 +69,9 @@ public:
     int numLoadedEventTypes() const override;
     void addEventType(const QQmlProfilerEventType &type) override;
     void addEvent(const QQmlProfilerEvent &event) override;
+
+private:
+    qint64 lastTimestamp = -1;
 };
 
 void QQmlProfilerTestClient::startTrace(qint64 timestamp, const QList<int> &engineIds)
@@ -102,6 +105,9 @@ void QQmlProfilerTestClient::addEvent(const QQmlProfilerEvent &event)
 
     const QQmlProfilerEventType &type = types[typeIndex];
 
+    QVERIFY(event.timestamp() >= lastTimestamp);
+    lastTimestamp = event.timestamp();
+
     switch (type.message()) {
     case Event: {
         switch (type.detailType()) {