contractcourt+itest: make sure ChannelArbitrator has the latest htlcs

contractcourt/chain_arbitrator.go

@@ -1287,6 +1287,10 @@ func (c *ChainArbitrator) FindOutgoingHTLCDeadline(scid lnwire.ShortChannelID,
 			continue
 		}
 
+		// Make sure the channel arbitrator has the latest view of its
+		// active HTLCs.
+		channelArb.updateActiveHTLCs()
+
 		// Iterate all the known HTLCs to find the targeted incoming
 		// HTLC.
 		for _, htlcs := range channelArb.activeHTLCs {

contractcourt/channel_arbitrator.go

@@ -3089,6 +3089,9 @@ func (c *ChannelArbitrator) channelAttendant(bestHeight int32) {
 		// We've just received a request to forcibly close out the
 		// channel. We'll
 		case closeReq := <-c.forceCloseReqs:
+			log.Infof("ChannelArbitrator(%v): received force "+
+				"close request", c.cfg.ChanPoint)
+
 			if c.state != StateDefault {
 				select {
 				case closeReq.closeTx <- nil:

itest/lnd_multi-hop_test.go

@@ -713,12 +713,6 @@ func runMultiHopLocalForceCloseOnChainHtlcTimeout(ht *lntest.HarnessTest,
 	// to be mined to trigger a force close later on.
 	var blocksMined uint32
 
-	// We need to mine a block otherwise `FindOutgoingHTLCDeadline` cannot
-	// find the incoming HTLC on Bob's ChainArbitrator.
-	//
-	// TODO(yy): Investigate and fix it!
-	ht.MineEmptyBlocks(1)
-
 	// Now that all parties have the HTLC locked in, we'll immediately
 	// force close the Bob -> Carol channel. This should trigger contract
 	// resolution mode for both of them.