message: Monitoring: Fix the initial time range rendered by graphs
  Fix `this.timeSpan` to have the correct initial value. Fixes a bug where
  time range `props.timeSpan` was plotted instead of `this.defaultSpan`.
diff: @@ -16,6 +16,7 @@ class QueryBrowser_ extends Line_ {
  // For the default time span, use the first of the suggested span options that is at least as long as props.timeSpan
  this.defaultSpan = spans.map(parsePrometheusDuration).find(s => s >= props.timeSpan);
  + this.timeSpan = this.defaultSpan;
  _.assign(this.state, {
  isSpanValid: true,
  