eth, les: Refactor downloader peer to use structs

eth/downloader/statesync.go

@@ -37,7 +37,7 @@ type stateReq struct {
 	tasks    map[common.Hash]*stateTask // Download tasks to track previous attempts
 	timeout  time.Duration              // Maximum round trip time for this to complete
 	timer    *time.Timer                // Timer to fire when the RTT timeout expires
-	peer     *peer                      // Peer that we're requesting from
+	peer     *peerConnection            // Peer that we're requesting from
 	response [][]byte                   // Response data of the peer (nil for timeouts)
 }
 
@@ -246,7 +246,7 @@ func (s *stateSync) Cancel() error {
 // and timeouts.
 func (s *stateSync) loop() error {
 	// Listen for new peer events to assign tasks to them
-	newPeer := make(chan *peer, 1024)
+	newPeer := make(chan *peerConnection, 1024)
 	peerSub := s.d.peers.SubscribeNewPeers(newPeer)
 	defer peerSub.Unsubscribe()