Add router that does nothing for bitswap_wo_routing test

License: MIT
Signed-off-by: Karthik Bala <karthikbala444@gmail.com>

none/none_client.go

+package nilrouting
+
+import (
+	"errors"
+
+	ds "github.com/ipfs/go-ipfs/Godeps/_workspace/src/github.com/jbenet/go-datastore"
+	context "github.com/ipfs/go-ipfs/Godeps/_workspace/src/golang.org/x/net/context"
+	key "github.com/ipfs/go-ipfs/blocks/key"
+	p2phost "github.com/ipfs/go-ipfs/p2p/host"
+	peer "github.com/ipfs/go-ipfs/p2p/peer"
+	routing "github.com/ipfs/go-ipfs/routing"
+	u "github.com/ipfs/go-ipfs/util"
+)
+
+var log = u.Logger("mockrouter")
+
+type nilclient struct {
+}
+
+func (c *nilclient) PutValue(_ context.Context, _ key.Key, _ []byte) error {
+	return nil
+}
+
+func (c *nilclient) GetValue(_ context.Context, _ key.Key) ([]byte, error) {
+	return nil, errors.New("Tried GetValue from nil routing.")
+}
+
+func (c *nilclient) FindPeer(_ context.Context, _ peer.ID) (peer.PeerInfo, error) {
+	return peer.PeerInfo{}, nil
+}
+
+func (c *nilclient) FindProvidersAsync(_ context.Context, _ key.Key, _ int) <-chan peer.PeerInfo {
+	out := make(chan peer.PeerInfo)
+	defer close(out)
+	return out
+}
+
+func (c *nilclient) Provide(_ context.Context, _ key.Key) error {
+	return nil
+}
+
+func (c *nilclient) Bootstrap(_ context.Context) error {
+	return nil
+}
+
+func ConstructNilRouting(_ context.Context, _ p2phost.Host, _ ds.ThreadSafeDatastore) (routing.IpfsRouting, error) {
+	return &nilclient{}, nil
+}
+
+//  ensure nilclient satisfies interface
+var _ routing.IpfsRouting = &nilclient{}