Revert of Remove NPAPI plugin from chromoting webapp.

remoting/webapp/host_it2me_dispatcher.js

Index: remoting/webapp/host_it2me_dispatcher.js
diff --git a/remoting/webapp/host_it2me_dispatcher.js b/remoting/webapp/host_it2me_dispatcher.js
index bd75a4f88de70aff02057d47b6a081964d3558f9..3c2fce7762380181038c9bc5921a916ed42dfc74 100644
--- a/remoting/webapp/host_it2me_dispatcher.js
+++ b/remoting/webapp/host_it2me_dispatcher.js
@@ -5,9 +5,12 @@
 /**
  * @fileoverview
  * This class provides an interface between the HostSession and either the
- * NativeMessaging Host
+ * NativeMessaging Host or the Host NPAPI plugin, depending on whether or not
+ * NativeMessaging is supported. Since the test for NativeMessaging support is
+ * asynchronous, the connection is attemped on either the the NativeMessaging
+ * host or the NPAPI plugin once the test is complete.
  *
- * TODO(sergeyu): Remove this class.
+ * TODO(sergeyu): Remove this class once the NPAPI plugin is dropped.
  */
 
 'use strict';
@@ -25,12 +28,20 @@
   this.nativeMessagingHost_ = null;
 
   /**
+   * @type {remoting.HostPlugin}
+   * @private */
+  this.npapiHost_ = null;
+
+  /**
    * @param {remoting.Error} error
    * @private */
   this.onErrorHandler_ = function(error) {}
 };
 
 /**
+ * @param {function():remoting.HostPlugin} createPluginCallback Callback to
+ *     instantiate the NPAPI plugin when NativeMessaging is determined to be
+ *     unsupported.
  * @param {function():void} onDispatcherInitialized Callback to be called after
  *     initialization has finished successfully.
  * @param {function(remoting.Error):void} onDispatcherInitializationFailed
@@ -38,18 +49,31 @@
  *     plugin works.
  */
 remoting.HostIt2MeDispatcher.prototype.initialize =
-    function(onDispatcherInitialized,
+    function(createPluginCallback, onDispatcherInitialized,
              onDispatcherInitializationFailed) {
   /** @type {remoting.HostIt2MeDispatcher} */
   var that = this;
 
   function onNativeMessagingStarted() {
+    console.log('Native Messaging supported.');
+
+    that.npapiHost_ = null;
     onDispatcherInitialized();
   }
 
   function onNativeMessagingInitFailed() {
+    console.log('Native Messaging unsupported, falling back to NPAPI.');
+
     that.nativeMessagingHost_ = null;
-    onDispatcherInitializationFailed(remoting.Error.MISSING_PLUGIN);
+    that.npapiHost_ = createPluginCallback();
+
+    // TODO(weitaosu): is there a better way to check whether NPAPI plugin is
+    // supported?
+    if (that.npapiHost_) {
+      onDispatcherInitialized();
+    } else {
+      onDispatcherInitializationFailed(remoting.Error.MISSING_PLUGIN);
+    }
   }
 
   this.nativeMessagingHost_ = new remoting.HostIt2MeNativeMessaging();
@@ -65,6 +89,20 @@
     function(error) {
   this.nativeMessagingHost_ = null;
   this.onErrorHandler_(error);
+}
+
+/**
+ * @return {boolean}
+ */
+remoting.HostIt2MeDispatcher.prototype.usingNpapi = function() {
+  return this.npapiHost_ != null;
+}
+
+/**
+ * @return {remoting.HostPlugin}
+ */
+remoting.HostIt2MeDispatcher.prototype.getNpapiHost = function() {
+  return this.npapiHost_;
 }
 
 /**
@@ -95,6 +133,15 @@
     this.nativeMessagingHost_.connect(
         email, authServiceWithToken, onStateChanged, onNatPolicyChanged,
         xmppServerAddress, xmppServerUseTls, directoryBotJid);
+  } else if (this.npapiHost_) {
+    this.npapiHost_.xmppServerAddress = xmppServerAddress;
+    this.npapiHost_.xmppServerUseTls = xmppServerUseTls;
+    this.npapiHost_.directoryBotJid = directoryBotJid;
+    this.npapiHost_.onStateChanged = onStateChanged;
+    this.npapiHost_.onNatTraversalPolicyChanged = onNatPolicyChanged;
+    this.npapiHost_.logDebugInfo = logDebugInfo;
+    this.npapiHost_.localize(chrome.i18n.getMessage);
+    this.npapiHost_.connect(email, authServiceWithToken);
   } else {
     console.error(
         'remoting.HostIt2MeDispatcher.connect() without initialization.');
@@ -106,26 +153,51 @@
  * @return {void}
  */
 remoting.HostIt2MeDispatcher.prototype.disconnect = function() {
-  this.nativeMessagingHost_.disconnect();
+  if (this.npapiHost_) {
+    this.npapiHost_.disconnect();
+  } else {
+    this.nativeMessagingHost_.disconnect();
+  }
 };
 
 /**
  * @return {string} The access code generated by the it2me host.
  */
 remoting.HostIt2MeDispatcher.prototype.getAccessCode = function() {
-  return this.nativeMessagingHost_.getAccessCode();
+  if (this.npapiHost_) {
+    return this.npapiHost_.accessCode;
+  } else {
+    return this.nativeMessagingHost_.getAccessCode();
+  }
 };
 
 /**
  * @return {number} The access code lifetime, in seconds.
  */
 remoting.HostIt2MeDispatcher.prototype.getAccessCodeLifetime = function() {
-  return this.nativeMessagingHost_.getAccessCodeLifetime();
+  if (this.npapiHost_) {
+    return this.npapiHost_.accessCodeLifetime;
+  } else {
+    return this.nativeMessagingHost_.getAccessCodeLifetime();
+  }
 };
 
 /**
  * @return {string} The client's email address.
  */
 remoting.HostIt2MeDispatcher.prototype.getClient = function() {
-  return this.nativeMessagingHost_.getClient();
-};
+  if (this.npapiHost_) {
+    return this.npapiHost_.client;
+  } else {
+    return this.nativeMessagingHost_.getClient();
+  }
+};
+
+/**
+ * @return {void}
+ */
+remoting.HostIt2MeDispatcher.prototype.cleanup = function() {
+  if (this.npapiHost_) {
+    this.npapiHost_.parentNode.removeChild(this.npapiHost_);
+  }
+};