QmlProfiler: Allow only one category per model in timeline

This simplifies the code a lot and allows for more flexibility
when interacting with the data.

Change-Id: I69630071eee66840e905fcd95ba8c708742d58b6
Reviewed-by: Kai Koehne <kai.koehne@digia.com>

src/plugins/qmlprofiler/abstracttimelinemodel.cpp

@@ -57,14 +57,6 @@ void AbstractTimelineModel::setModelManager(QmlProfilerModelManager *modelManage
     d->modelId = d->modelManager->registerModelProxy();
 }
 
-QStringList AbstractTimelineModel::categoryTitles() const
-{
-    QStringList retString;
-    for (int i = 0; i < categoryCount(); i++)
-        retString << categoryLabel(i);
-    return retString;
-}
-
 QString AbstractTimelineModel::name() const
 {
     Q_D(const AbstractTimelineModel);
@@ -169,14 +161,6 @@ int AbstractTimelineModel::getEventIdForLocation(const QString &filename, int li
     return -1;
 }
 
-int AbstractTimelineModel::rowCount() const
-{
-    int count = 0;
-    for (int i=0; i<categoryCount(); i++)
-        count += categoryDepth(i);
-    return count;
-}
-
 int AbstractTimelineModel::getBindingLoopDest(int index) const
 {
     Q_UNUSED(index);