Follow code review suggestions

internal/buffer/unbounded_test.go

@@ -120,7 +120,8 @@ func (s) TestMultipleWriters(t *testing.T) {
 	}
 }
 
-// TestClose makes sure that the buffer is closed after calling Close().
+// TestClose closes the buffer and makes sure that nothing is sent after the
+// buffer is closed.
 func (s) TestClose(t *testing.T) {
 	ub := NewUnbounded()
 	ub.Close()
@@ -133,7 +134,4 @@ func (s) TestClose(t *testing.T) {
 		t.Errorf("Unbounded.Get() = %v, want closed channel", v)
 	}
 	ub.Close()
-	if v, ok := <-ub.Get(); ok {
-		t.Errorf("Unbounded.Get() = %v, want closed channel", v)
-	}
 }

xds/internal/balancer/outlierdetection/balancer.go

@@ -366,10 +366,10 @@ func (b *outlierDetectionBalancer) Close() {
 	b.pickerUpdateCh.Close()
 
 	b.mu.Lock()
+	defer b.mu.Unlock()
 	if b.intervalTimer != nil {
 		b.intervalTimer.Stop()
 	}
-	b.mu.Unlock()
 }
 
 func (b *outlierDetectionBalancer) ExitIdle() {

xds/internal/xdsclient/transport/transport.go

@@ -402,7 +402,7 @@ func (t *Transport) send(ctx context.Context) {
 			sendNodeProto = false
 		case u, ok := <-t.adsRequestCh.Get():
 			if !ok {
-				// No requests will be sent after the unbounded buffer is closed.
+				// No requests will be sent after the adsRequestCh buffer is closed.
 				return
 			}
 			t.adsRequestCh.Load()