style(net) rm unused error

having an error return value makes the interface a bit confusing to
use. Just ponder... What would an error returned from a predicate
function mean?

License: MIT
Signed-off-by: Brian Tiger Chow <brian@perfmode.com>

net/interface.go

@@ -27,7 +27,7 @@ type Network interface {
 	ClosePeer(peer.Peer) error
 
 	// IsConnected returns whether a connection to given peer exists.
-	IsConnected(peer.Peer) (bool, error)
+	IsConnected(peer.Peer) bool
 
 	// GetProtocols returns the protocols registered in the network.
 	GetProtocols() *mux.ProtocolMap

net/net.go

@@ -75,8 +75,8 @@ func (n *IpfsNetwork) ClosePeer(p peer.Peer) error {
 }
 
 // IsConnected returns whether a connection to given peer exists.
-func (n *IpfsNetwork) IsConnected(p peer.Peer) (bool, error) {
-	return n.swarm.GetConnection(p.ID()) != nil, nil
+func (n *IpfsNetwork) IsConnected(p peer.Peer) bool {
+	return n.swarm.GetConnection(p.ID()) != nil
 }
 
 // GetProtocols returns the protocols registered in the network.