calculate pin list checksums in a worker

lib/commands/pin-rpc.js

@@ -142,23 +142,9 @@ var getFreeSpace = Pinning.getFreeSpace = function (Env, safeKey, cb) {
     });
 };
 
-var hashChannelList = function (A) {
-    var uniques = [];
-
-    A.forEach(function (a) {
-        if (uniques.indexOf(a) === -1) { uniques.push(a); }
-    });
-    uniques.sort();
-
-    var hash = Nacl.util.encodeBase64(Nacl.hash(Nacl
-        .util.decodeUTF8(JSON.stringify(uniques))));
-
-    return hash;
-};
-
 var getHash = Pinning.getHash = function (Env, safeKey, cb) {
     getChannelList(Env, safeKey, function (channels) {
-        cb(void 0, hashChannelList(channels));
+        Env.hashChannelList(channels, cb);
     });
 };