DevTools: follow up to r168484, do not add same parent twice into flame chart.

Source/devtools/front_end/TimelineFlameChart.js

Index: Source/devtools/front_end/TimelineFlameChart.js
diff --git a/Source/devtools/front_end/TimelineFlameChart.js b/Source/devtools/front_end/TimelineFlameChart.js
index 57558cad0280c1966d0e18d797f2bd4cdfe2af2b..abb0e22b5a89ccd94107f9d29009356d27d072f1 100644
--- a/Source/devtools/front_end/TimelineFlameChart.js
+++ b/Source/devtools/front_end/TimelineFlameChart.js
@@ -221,7 +221,7 @@ WebInspector.TimelineFlameChartDataProvider.prototype = {
             this._appendRecord(childRecord, level + 1);
             currentTime = childEndTime;
         }
-        if (recordEndTime !== currentTime || record.children.length === 0)
+        if (recordIndex === -1 && recordEndTime !== currentTime || record.children.length === 0)
             this._pushRecord(record, true, level, currentTime, recordEndTime);
 
         this._maxStackDepth = Math.max(this._maxStackDepth, level + 2);