message: fix for loop - check happens before pre-inc so cause issues at end of TL
diff: @@ -1023,7 +1023,7 @@ var TimelinePanel = React.createClass({
  let latestReadEventIndex = i;
  // Place the RM at a hidden event below the latest seen event (if exists)
  // to prevent RM going up the timeline between clients which do not hide the same events.
  - for (let j = i; j < this.state.events.length; ++j) {
  + for (let j = i + 1; j < this.state.events.length; j++) {
  if (messagePanel._shouldShowEvent(this.state.events[j])) break;
  latestReadEventIndex = j;
  }
  