[Chromoting] Factor out common code for pin hashing.

remoting/webapp/host_controller.js

 // Copyright (c) 2012 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 'use strict';
 
 /** @suppress {duplicate} */
 var remoting = remoting || {};
 
 /** @constructor */
@@ skipping 134 matching lines @@
     callback(result);
   };
 
   /** @param {string} privateKey
    *  @param {XMLHttpRequest} xhr */
   function onRegistered(privateKey, xhr) {
     var success = (xhr.status == 200);
 
     if (success) {
       var hostSecretHash =
-          'hmac:' + that.plugin_.getPinHash(newHostId, hostPin);
+          that.plugin_.getPinHash(newHostId, hostPin);
       var hostConfig = JSON.stringify({
           xmpp_login: remoting.oauth2.getCachedEmail(),
           oauth_refresh_token: remoting.oauth2.exportRefreshToken(),
           oauth_use_official_client_id:
               remoting.oauth2.USE_OFFICIAL_CLIENT_ID,
           host_id: newHostId,
           host_name: hostName,
           host_secret_hash: hostSecretHash,
           private_key: privateKey
       });
@@ skipping 101 matching lines @@
 
   /** @param {string} configStr */
   function onConfig(configStr) {
     var config = parseHostConfig_(configStr);
     if (!config) {
       callback(remoting.HostController.AsyncResult.FAILED);
       return;
     }
     var hostId = config['host_id'];
     var newConfig = JSON.stringify({
-        host_secret_hash: 'hmac:' + that.plugin_.getPinHash(hostId, newPin)
+        host_secret_hash: that.plugin_.getPinHash(hostId, newPin)
       });
     that.plugin_.updateDaemonConfig(newConfig, callback);
   };
 
   // TODO(sergeyu): When crbug.com/121518 is fixed: replace this call
   // with an upriveleged version if that is necessary.
   this.plugin_.getDaemonConfig(onConfig);
 };
 
 /**
@@ skipping 60 matching lines @@
   try {
     this.plugin_.getDaemonConfig(onConfig);
   } catch (err) {
     this.setHost(null);
     onDone();
   }
 };
 
 /** @type {remoting.HostController} */
 remoting.hostController = null;