use leveldown staging.

lib/bcoin/chaindb.js

@@ -1254,8 +1254,6 @@ ChainDB.prototype._getTX = function _getTX(hash, callback) {
 // For BIP30
 // https://bitcointalk.org/index.php?topic=67738.0
 ChainDB.prototype.isUnspentTX = function isUnspentTX(hash, callback) {
-  return callback(null, false);
-
   if (this.options.spv)
     return callback(null, false);
 

lib/bcoin/fullnode.js

@@ -110,7 +110,6 @@ Fullnode.prototype._init = function _init() {
   });
 
   this.on('tx', function(tx) {
-    return;
     self.walletdb.addTX(tx, function(err) {
       if (err)
         self.emit('error', err);

package.json

@@ -30,7 +30,7 @@
   "dependencies": {
     "bn.js": "4.11.0",
     "elliptic": "6.2.3",
-    "leveldown": "git://github.com/Level/leveldown.git#master"
+    "leveldown": "git://github.com/chjj/leveldown.git#staging"
   },
   "optionalDependencies": {
     "secp256k1": "3.0.0",