opts.endTime = g.EndTime.Sub(parsed.startTime())
			} else { // The goroutine didn't end.
				opts.endTime = parsed.endTime().Sub(parsed.startTime())
			}
			opts.focusGoroutine = goid
			opts.goroutines = trace.RelatedGoroutinesV2(parsed.events, goid)
		} else if taskids := r.FormValue("focustask"); taskids != "" {
			taskid, err := strconv.ParseUint(taskids, 10, 64)
			if err != nil {

	}
	return &Summary{
		Goroutines: s.gs,
		Tasks:      s.tasks,
	}
}

// RelatedGoroutinesV2 finds a set of goroutines related to goroutine goid for v2 traces.
// The association is based on whether they have synchronized with each other in the Go
// scheduler (one has unblocked another).
func RelatedGoroutinesV2(events []Event, goid GoID) map[GoID]struct{} {
	// Process all the events, looking for transitions of goroutines

		}
		if err != nil {
			t.Fatalf("failed to process trace %s: %v", testPath, err)
		}
		events = append(events, ev)
	}

	// Test the function.
	targetg := trace.GoID(86)
	got := trace.RelatedGoroutinesV2(events, targetg)
	want := map[trace.GoID]struct{}{
		trace.GoID(86):  struct{}{}, // N.B. Result includes target.
		trace.GoID(71):  struct{}{},
		trace.GoID(25):  struct{}{},
		trace.GoID(122): struct{}{},
	}