Draw every panel figure from the latest sample instead of holding the totals

main_test.go

@@ -1,9 +1,6 @@
 package main
 
-import (
-	"testing"
-	"time"
-)
+import "testing"
 
 // A reset re-bases from a fresh capture while the ring still holds buckets from
 // just before it, so the newest bucket must not be left behind the new origin.
@@ -22,7 +19,7 @@ func TestResetDoesNotUnderflowTotals(t *testing.T) {
 	d.rxStats[0].bytes.Store(9600)
 	d.reset()
 
-	v := d.displayView(time.Now())
+	v := d.displayView()
 	if v.rxFrames != 0 {
 		t.Errorf("rxFrames = %d, want 0", v.rxFrames)
 	}