cnct: dispatch contract breach after channel close summary is serialized

This commit moves the contract breach event dispatch after the channel
close summary has been added to the database. This is important
otherwise it may occur that we attempt to mark the channel fully closed
while the channel close summary is not yet serialized.

contractcourt/chain_watcher.go

@@ -1128,19 +1128,6 @@ func (c *chainWatcher) dispatchContractBreach(spendEvent *chainntnfs.SpendDetail
 		return err
 	}
 
-	// With the event processed, we'll now notify all subscribers of the
-	// event.
-	c.Lock()
-	for _, sub := range c.clientSubscriptions {
-		select {
-		case sub.ContractBreach <- retribution:
-		case <-c.quit:
-			c.Unlock()
-			return fmt.Errorf("quitting")
-		}
-	}
-	c.Unlock()
-
 	// At this point, we've successfully received an ack for the breach
 	// close. We now construct and persist  the close summary, marking the
 	// channel as pending force closed.
@@ -1182,6 +1169,19 @@ func (c *chainWatcher) dispatchContractBreach(spendEvent *chainntnfs.SpendDetail
 	log.Infof("Breached channel=%v marked pending-closed",
 		c.cfg.chanState.FundingOutpoint)
 
+	// With the event processed and channel closed, we'll now notify all
+	// subscribers of the event.
+	c.Lock()
+	for _, sub := range c.clientSubscriptions {
+		select {
+		case sub.ContractBreach <- retribution:
+		case <-c.quit:
+			c.Unlock()
+			return fmt.Errorf("quitting")
+		}
+	}
+	c.Unlock()
+
 	return nil
 }