Get host id via getDaemonConfig.

remoting/webapp/host_controller.js

Index: remoting/webapp/host_controller.js
diff --git a/remoting/webapp/host_controller.js b/remoting/webapp/host_controller.js
index ab76339dc179382e21b6bcae80a26443a96c7947..db8bbe41beef797277864f04b8210e57ffe2b1b3 100644
--- a/remoting/webapp/host_controller.js
+++ b/remoting/webapp/host_controller.js
@@ -120,9 +120,6 @@ remoting.HostController.prototype.start = function(hostPin, callback) {
   };
 
   var newHostId = generateUuid();
-  // TODO(jamiewalch): Create an unprivileged API to get the host id from the
-  // plugin instead of storing it locally (crbug.com/121518).
-  window.localStorage.setItem('me2me-host-id', newHostId);
 
   /** @param {function(remoting.HostController.AsyncResult):void} callback
    *  @param {remoting.HostController.AsyncResult} result
@@ -224,7 +221,6 @@ remoting.HostController.prototype.stop = function(callback) {
   function onStopped(result) {
     if (that.localHost && that.localHost.hostId)
       remoting.HostList.unregisterHostById(that.localHost.hostId);
-    window.localStorage.removeItem('me2me-host-id');
     callback(result);
   };
   this.plugin_.stopDaemon(onStopped);
@@ -304,20 +300,24 @@ remoting.HostController.prototype.setHost = function(host) {
  *
  * @param {remoting.HostList} hostList The new host list, returned by the
  *     Chromoting service.
- * @param {function():void} onDone Completion callback. TODO(jamiewalch): For
- *     now, this is synchronous and reads the host id from local storage. In
- *     the future, it will asynchronously read the host id from the plugin
- *     (crbug.com/121518).
+ * @param {function():void} onDone Completion callback.
  */
 remoting.HostController.prototype.onHostListRefresh =
     function(hostList, onDone) {
-  var hostId = window.localStorage.getItem('me2me-host-id');
-  if (hostId && typeof(hostId) == 'string') {
-    this.setHost(hostList.getHostForId(/** @type{string} */(hostId)));
-  } else {
-    this.setHost(null);
-  }
-  onDone();
+  /** @type {remoting.HostController} */
+  var that = this;
+  /** @param {string} configStr */
+  function onConfig(configStr) {
+    var config = /** @type {Object.<string,string>} */ JSON.parse(configStr);
+    if (('host_id' in config) && typeof config['host_id'] == 'string') {
+      var hostId = config['host_id'];

[simonmorris, 2012/04/23 17:29:18]

It's less repetitive to test for hostId not being undefined. I think 'if
(hostId) { ... }' can replace the previous 'if'. For optional awesomeness, make
getHostForId map undefined to null, and remove the 'if' entirely.

[Jamie, 2012/04/23 20:24:25]

I want to check that host_id is a string, but you're right that there's no need
for an existence-check so I've removed that. I'm not sure I like the idea of
making getHostForId check for undefined, if only because it would effectively
make the hostId parameter optional (at least from a JSDoc point-of-view) and we
don't want that.

Of course, this is largely moot because getHostForId will return NULL for
anything the 'if' filters, and it's hard to imagine it ever doing anything else,
but I'd rather not rely on that.

+      that.setHost(hostList.getHostForId(hostId));
+    } else {
+      that.setHost(null);
+    }
+    onDone();
+  };
+  this.plugin_.getDaemonConfig(onConfig);
 };
 
 /** @type {remoting.HostController} */