No need to qualify calls to SortedTimelineModel::clear()

Task-number: QTCREATORBUG-12010
Change-Id: I22bc4525329f50359e6857c595fe686af901711e
Reviewed-by: Kai Koehne <kai.koehne@digia.com>

plugins/qmlprofilerextension/pixmapcachemodel.cpp

@@ -489,7 +489,7 @@ void PixmapCacheModel::loadData()
 void PixmapCacheModel::clear()
 {
     Q_D(PixmapCacheModel);
-    d->SortedTimelineModel::clear();
+    d->clear();
     d->pixmaps.clear();
     d->collapsedRowCount = 1;
     d->maxCacheSize = 1;