Read tier 1's build and the note once the plan has reached them in the silent middle tier test (issue 1160)

cmd/mesh-controller/silent_mid_tier_integration_test.go

@@ -185,10 +185,20 @@ func TestAPlanPassesATierWhoseMachineNeverReportsAfterTheBoundAndSendsTheNextToT
 	if got := plan().Tier; got != 0 {
 		t.Fatalf("1160/AC5: the plan went on to tier %d before the bound, with laptop not heard from", got)
 	}
-	eventually(t, "tier 1 asked once laptop's key expired", func() bool { return plan().Tier == 1 })
+	// The note of the move to tier 1 is read in the step that sees it: later steps of the tier say their own.
-	if note := plan().Note; !strings.Contains(note, "laptop") || strings.Contains(note, "anchor") {
+	var moved string
-		t.Errorf("1160/AC5: the plan says %q; want laptop named silent and not anchor", note)
+	eventually(t, "tier 1 passed once laptop's key expired", func() bool {
+		if q := plan(); q.Tier == 1 {
+			moved = q.Note
+			return true
+		}
+		return false
+	})
+	if !strings.Contains(moved, "laptop") || strings.Contains(moved, "anchor") {
+		t.Errorf("1160/AC5: the plan says %q; want laptop named silent and not anchor", moved)
 	}
+	// The ask for tier 1's build is the next step, and records its build id on the module.
+	eventually(t, "tier 1 asked", func() bool { m := plan().Modules["b"]; return m != nil && m.Build != "" })
 	b := plan().Modules["b"]
 	askedAt, _ := link.BuildAskedAt(b.Build)
 	record(b.Build, "b", "c2", askedAt)