gistfile1.txt

diff --git a/toolkit/components/extensions/Extension.jsm b/toolkit/components/extensions/Extension.jsm
--- a/toolkit/components/extensions/Extension.jsm
+++ b/toolkit/components/extensions/Extension.jsm
@@ -1198,21 +1198,23 @@ this.Extension.generateXPI = function(id
 /**
  * A skeleton Extension-like object, used for testing, which installs an
  * add-on via the add-on manager when startup() is called, and
  * uninstalles it on shutdown().
  *
  * @param {string} id
  * @param {nsIFile} file
  * @param {nsIURI} rootURI
+ * @param {string} installType
  */
-function MockExtension(id, file, rootURI) {
+function MockExtension(id, file, rootURI, installType) {
   this.id = id;
   this.file = file;
   this.rootURI = rootURI;
+  this.installType = installType;
 
   let promiseEvent = eventName => new Promise(resolve => {
     let onstartup = (msg, extension) => {
       if (extension.id == this.id) {
         Management.off(eventName, onstartup);
 
         this._extension = extension;
         resolve(extension);
@@ -1239,20 +1241,48 @@ MockExtension.prototype = {
 
   off(...args) {
     this._extensionPromise.then(extension => {
       extension.off(...args);
     });
   },
 
   startup() {
-    return AddonManager.installTemporaryAddon(this.file).then(addon => {
-      this.addon = addon;
-      return this._readyPromise;
-    });
+    if (this.installType == "temporary") {
+      return AddonManager.installTemporaryAddon(this.file).then(addon => {
+        this.addon = addon;
+        return this._readyPromise;
+      });
+    } else if (this.installType == "permanent") {
+      let installCompleted = (install) => {
+        install.removeListener(listener);
+        return new Promise(resolve => {
+          AddonManager.getAddonByID(this.id, resolve).then(addon => {
+            this.addon = addon;
+            return this._readyPromise;
+          });
+        });
+      };
+
+      let listener = {
+        onDownloadFailed: installCompleted,
+        onDownloadCancelled: installCompleted,
+        onInstallFailed: installCompleted,
+        onInstallCancelled: installCompleted,
+        onInstallEnded: installCompleted,
+        onInstallPostponed: installCompleted,
+      };
+
+      AddonManager.getInstallForFile(this.file, install => {
+        install.addListener(listener);
+        install.install();
+      });
+    } else {
+      throw Error("installType must be one of: temporary, permanent");
+    }
   },
 
   shutdown() {
     this.addon.uninstall(true);
     return this.cleanupGeneratedFile();
   },
 
   cleanupGeneratedFile() {
@@ -1273,18 +1303,19 @@ this.Extension.generate = function(id, d
   let file = this.generateXPI(id, data);
 
   flushJarCache(file);
   Services.ppmm.broadcastAsyncMessage("Extension:FlushJarCache", {path: file.path});
 
   let fileURI = Services.io.newFileURI(file);
   let jarURI = Services.io.newURI("jar:" + fileURI.spec + "!/", null, null);
 
+  // this may be "temporary" or "permanent".
   if (data.useAddonManager) {
-    return new MockExtension(id, file, jarURI);
+    return new MockExtension(id, file, jarURI, data.useAddonManager);
   }
 
   return new Extension({
     id,
     resourceURI: jarURI,
     cleanupFile: file,
   });
 };
diff --git a/toolkit/components/extensions/test/mochitest/test_chrome_ext_background_debug_global.html b/toolkit/components/extensions/test/mochitest/test_chrome_ext_background_debug_global.html
--- a/toolkit/components/extensions/test/mochitest/test_chrome_ext_background_debug_global.html
+++ b/toolkit/components/extensions/test/mochitest/test_chrome_ext_background_debug_global.html
@@ -30,17 +30,17 @@ const {
  */
 
 function backgroundScript() {
   window.testThing = "test!";
   browser.test.notifyPass("background script ran");
 }
 
 let extensionData = {
-  useAddonManager: true,
+  useAddonManager: "temporary",
   background: "(" + backgroundScript.toString() + ")()",
   manifest: {},
   files: {},
 };
 
 add_task(function* () {
   let extension = ExtensionTestUtils.loadExtension(extensionData);
   yield extension.startup();