Fix HostDaemonFacade to handle the case when NM host is not installed.

remoting/webapp/host_daemon_facade.js

 // Copyright 2014 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.
 
 /**
  * @fileoverview
  * Class to communicate with the host daemon via Native Messaging.
  */
 
 'use strict';
@@ skipping 25 matching lines @@
 
   /** @type {Array.<remoting.HostController.Feature>} @private */
   this.supportedFeatures_ = [];
 
   /** @type {Array.<function(boolean):void>} @private */
   this.afterInitializationTasks_ = [];
 
   /** @private */
   this.initializationFinished_ = false;
 
+  /** @type {remoting.Error} @private */
+  this.error_ = remoting.Error.NONE;
+
   try {
     this.port_ = chrome.runtime.connectNative(
         'com.google.chrome.remote_desktop');
     this.port_.onMessage.addListener(this.onIncomingMessage_.bind(this));
     this.port_.onDisconnect.addListener(this.onDisconnect_.bind(this));
     this.postMessage_({type: 'hello'},
                       this.onInitialized_.bind(this, true),
                       this.onInitialized_.bind(this, false));
   } catch (err) {
     console.log('Native Messaging initialization failed: ',
@@ skipping 17 matching lines @@
   this.onError = onError;
 };
 
 /**
  * @param {boolean} success
  * @return {void} Nothing.
  * @private
  */
 remoting.HostDaemonFacade.prototype.onInitialized_ = function(success) {
   this.initializationFinished_ = true;
-  if (!success) {
-    this.port_ = null;
-  }
-
   var afterInitializationTasks = this.afterInitializationTasks_;
   this.afterInitializationTasks_ = [];
   for (var id in afterInitializationTasks) {
     afterInitializationTasks[/** @type {number} */(id)](success);
   }
 };
 
 /**
  * @param {remoting.HostController.Feature} feature The feature to test for.
  * @param {function(boolean):void} onDone Callback to return result.
@@ skipping 24 matching lines @@
  * @param {{type: string}} message The message to post.
  * @param {function(...):void} onDone The callback, if any, to be triggered
  *     on response.
  * @param {function(remoting.Error):void} onError Callback to call on error.
  * @return {void} Nothing.
  * @private
  */
 remoting.HostDaemonFacade.prototype.postMessage_ =
     function(message, onDone, onError) {
   if (!this.port_) {
-    onError(remoting.Error.UNEXPECTED);
+    onError(this.error_);
     return;
   }
   var id = this.nextId_++;
   message['id'] = id;
   this.pendingReplies_[id] = new remoting.HostDaemonFacade.PendingReply(
     message.type + 'Response', onDone, onError);
   this.port_.postMessage(message);
 };
 
 /**
@@ skipping 131 matching lines @@
   }
 };
 
 /**
  * @return {void} Nothing.
  * @private
  */
 remoting.HostDaemonFacade.prototype.onDisconnect_ = function() {
   console.error('Native Message port disconnected');
 
+  this.port_ = null;
+
+  // If initialization hasn't finished then assume that the port was
+  // disconnected because Native Messaging host is not installed.
+  this.error_ = this.initializationFinished_ ? remoting.Error.UNEXPECTED :
+                                               remoting.Error.MISSING_PLUGIN;
+
   // Notify the error-handlers of any requests that are still outstanding.
   var pendingReplies = this.pendingReplies_;
   this.pendingReplies_ = {};
-
   for (var id in pendingReplies) {
-    pendingReplies[/** @type {number} */(id)].onError(
-        remoting.Error.UNEXPECTED);
+    pendingReplies[/** @type {number} */(id)].onError(this.error_);
   }
 }
 
 /**
  * Gets local hostname.
  *
  * @param {function(string):void} onDone Callback to return result.
  * @param {function(remoting.Error):void} onError Callback to call on error.
  * @return {void} Nothing.
  */
@@ skipping 85 matching lines @@
     onDone(this.version_);
   } else {
     /** @type remoting.HostDaemonFacade */
     var that = this;
     this.afterInitializationTasks_.push(
         /** @param {boolean} success */
         function(success) {
           if (success) {
             onDone(that.version_);
           } else {
-            onError(remoting.Error.UNEXPECTED);
+            onError(that.error_);
           }
         });
   }
 };
 
 /**
  * Get the user's consent to crash reporting. The consent flags are passed to
  * the callback as booleans: supported, allowed, set-by-policy.
  *
  * @param {function(boolean, boolean, boolean):void} onDone Callback to return
@@ skipping 108 matching lines @@
  * @param {function(remoting.Error):void} onError Callback to call on error.
  * @return {void} Nothing.
  */
 remoting.HostDaemonFacade.prototype.getCredentialsFromAuthCode =
     function(authorizationCode, onDone, onError) {
   this.postMessage_({
     type: 'getCredentialsFromAuthCode',
     authorizationCode: authorizationCode
   }, onDone, onError);
 };