Issue 5049 - Allow embedded WebExtensions in gecko packager

templates/bootstrap.js.tmpl

 /* This Source Code Form is subject to the terms of the Mozilla Public
  * License, v. 2.0. If a copy of the MPL was not distributed with this
  * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
 
 const Cc = Components.classes;
 const Ci = Components.interfaces;
 const Cr = Components.results;
 const Cu = Components.utils;
 
 let {Services} = Cu.import("resource://gre/modules/Services.jsm", {});
 
 Cu.importGlobalProperties(["atob", "btoa", "File", "URL",
     "TextDecoder", "TextEncoder", "XMLHttpRequest"]);
 
 let addonData = null;
 
 function startup(params, reason)
 {
   addonData = params;
 
   {%- if hasChromeRequires %}
   Services.obs.addObserver(RequireObserver, "{{metadata.get('general', 'basename')}}-require", true);
   onShutdown.add(function()
   {
     Services.obs.removeObserver(RequireObserver, "{{metadata.get('general', 'basename')}}-require");
   });
   {%- set hasShutdownHandlers = True %}
   {%- endif %}
 
+  {%- if hasWebExtension %}
+  let port = params.webExtension.startup().then(({browser}) =>
+  {
+    return new Promise((resolve, reject) =>
+    {
+      browser.runtime.onConnect.addListener(resolve);
+    });
+  });
+  require.scopes.webextension = {exports:  port};
+  {%- endif %}
+
   require("main");
 }
 
 function shutdown(params, reason)
 {
   {%- if chromeWindows %}
   let windowNames = {{chromeWindows|json}};
   for (let i = 0; i < windowNames.length; i++)
   {
     let enumerator = Services.wm.getEnumerator(windowNames[i]);
@@ skipping 136 matching lines @@
   {
     if (topic == "{{metadata.get('general', 'basename')}}-require")
     {
       subject.wrappedJSObject.exports = require(data);
     }
   },
 
   QueryInterface: XPCOMUtils.generateQI([Ci.nsISupportsWeakReference, Ci.nsIObserver])
 };
 {%- endif %}