Revert of Remove NPAPI plugin from chromoting webapp.

remoting/webapp/remoting.js

Index: remoting/webapp/remoting.js
diff --git a/remoting/webapp/remoting.js b/remoting/webapp/remoting.js
index 3772125bf72f32cd22ad45dbe2ba33339682a6cd..52357f7422128ea0c95e1239eafc0dc2fc9f73a9 100644
--- a/remoting/webapp/remoting.js
+++ b/remoting/webapp/remoting.js
@@ -179,6 +179,28 @@
 }
 
 /**
+ * Create an instance of the NPAPI plugin.
+ * @param {Element} container The element to add the plugin to.
+ * @return {remoting.HostPlugin} The new plugin instance or null if it failed to
+ *     load.
+ */
+remoting.createNpapiPlugin = function(container) {
+  var plugin = document.createElement('embed');
+  plugin.type = remoting.settings.PLUGIN_MIMETYPE;
+  // Hiding the plugin means it doesn't load, so make it size zero instead.
+  plugin.width = 0;
+  plugin.height = 0;
+
+  // Verify if the plugin was loaded successfully.
+  if (plugin.hasOwnProperty('REQUESTED_ACCESS_CODE')) {
+    container.appendChild(plugin);
+    return /** @type {remoting.HostPlugin} */ (plugin);
+  }
+
+  return null;
+};
+
+/**
  * Returns true if the current platform is fully supported. It's only used when
  * we detect that host native messaging components are not installed. In that
  * case the result of this function determines if the webapp should show the