Expose access to progress on f3 runner

The root F3 instance holds reference to the `gpbftRunner`, not
`gpbftHost`. To allow access to current progress from Lotus, move the
`Progress` implementation to runner and expose at root `F3` type.

Part of #599

f3.go

@@ -451,3 +451,12 @@ func (m *F3) GetPowerTable(ctx context.Context, ts gpbft.TipSetKey) (gpbft.Power
 
 	return nil, fmt.Errorf("no known network manifest")
 }
+
+func (m *F3) Progress() (instance, round uint64, phase gpbft.Phase) {
+	m.mu.Lock()
+	defer m.mu.Unlock()
+	if m.runner != nil {
+		instance, round, phase = m.runner.Progress()
+	}
+	return
+}

host.go

@@ -454,7 +454,7 @@ func (h *gpbftRunner) startPubsub() (<-chan gpbft.ValidatedMessage, error) {
 
 var (
 	_ gpbft.Host     = (*gpbftHost)(nil)
-	_ gpbft.Progress = (*gpbftHost)(nil).Progress
+	_ gpbft.Progress = (*gpbftRunner)(nil).Progress
 )
 
 // gpbftHost is a newtype of gpbftRunner exposing APIs required by the gpbft.Participant
@@ -493,6 +493,14 @@ func (h *gpbftRunner) Stop(context.Context) error {
 	)
 }
 
+// Progress returns the latest progress of GPBFT consensus in terms of instance
+// ID, round and phase.
+//
+// This API is safe for concurrent use.
+func (h *gpbftRunner) Progress() (instance, round uint64, phase gpbft.Phase) {
+	return h.participant.Progress()
+}
+
 // Returns inputs to the next GPBFT instance.
 // These are:
 // - the supplemental data.
@@ -777,11 +785,3 @@ func (h *gpbftHost) Verify(pubKey gpbft.PubKey, msg []byte, sig []byte) error {
 func (h *gpbftHost) Aggregate(pubKeys []gpbft.PubKey) (gpbft.Aggregate, error) {
 	return h.verifier.Aggregate(pubKeys)
 }
-
-// Progress returns the latest progress of GPBFT concensus in terms of instance
-// ID, round and phase.
-//
-// This API is safe for concurrent use.
-func (h *gpbftHost) Progress() (instance, round uint64, phase gpbft.Phase) {
-	return h.participant.Progress()
-}