Function collectCallEstablishmentTimings

collectCallEstablishmentTimings(mode, direction): ICallEstablishmentTimings
Collect all call establishment timings from performance marks. All times are measured from the 'new-call-start' mark.
Parameters
- mode: "trickle" | "non-trickle"
  
  'trickle' or 'non-trickle' ICE mode
- direction: "inbound" | "outbound"
  
  'outbound' or 'inbound'
Returns ICallEstablishmentTimings