common/registrar: delete the old registrar code

The registrar was broken, unmaintained and there is a much better
replacement: ENS.

(cherry picked from commit 6ca8f57b08)

eth/backend.go

@@ -32,7 +32,6 @@ import (
 	"github.com/ethereum/go-ethereum/accounts"
 	"github.com/ethereum/go-ethereum/common"
 	"github.com/ethereum/go-ethereum/common/httpclient"
-	"github.com/ethereum/go-ethereum/common/registrar/ethreg"
 	"github.com/ethereum/go-ethereum/core"
 	"github.com/ethereum/go-ethereum/core/types"
 	"github.com/ethereum/go-ethereum/eth/downloader"
@@ -127,7 +126,6 @@ type Ethereum struct {
 
 	eventMux       *event.TypeMux
 	pow            *ethash.Ethash
-	httpclient     *httpclient.HTTPClient
 	accountManager *accounts.Manager
 
 	ApiBackend *EthApiBackend
@@ -173,7 +171,6 @@ func New(ctx *node.ServiceContext, config *Config) (*Ethereum, error) {
 		pow:            pow,
 		shutdownChan:   make(chan bool),
 		stopDbUpgrade:  stopDbUpgrade,
-		httpclient:     httpclient.New(config.DocRoot),
 		netVersionId:   config.NetworkId,
 		NatSpec:        config.NatSpec,
 		PowTest:        config.PowTest,
@@ -356,10 +353,6 @@ func (s *Ethereum) APIs() []rpc.API {
 			Version:   "1.0",
 			Service:   s.netRPCService,
 			Public:    true,
-		}, {
-			Namespace: "admin",
-			Version:   "1.0",
-			Service:   ethreg.NewPrivateRegistarAPI(s.chainConfig, s.blockchain, s.chainDb, s.txPool, s.accountManager),
 		},
 	}...)
 }