When looking at Resources time graph, switching to size graph no longer shows the size summary graph.
Created attachment 41577 [details]
Screenshoot of the bug
Created attachment 41580 [details]
Created attachment 41597 [details]
Comment on attachment 41597 [details]
Just do: if (this.calculator.startAtZero || !this.calculator.computePercentageFromEventTime)
Committed in http://trac.webkit.org/changeset/49919.