Bug 40006: Fix new identity for 81

New identity tries to disable some buttons to prevent them from
being clicked while doing a new identity. These are now initialized
lazily, which makes the current code fail. Instead of doing that,
we now avoid disabling the buttons and ignore new identity requests
while one is in progress.

chrome/content/torbutton.js

@@ -760,15 +760,18 @@ torbutton_new_circuit = function() {
   gBrowser.reloadWithFlags(Ci.nsIWebNavigation.LOAD_FLAGS_BYPASS_CACHE);
 }
 
+let newIdentityInProgress = false;
+
 // Bug 1506 P4: Needed for New Identity.
 torbutton_new_identity = async function() {
   try {
-    // Make sure that we can only click once on New Identiy to avoid race
+    // Ignore if there's a New Identity in progress to avoid race
     // conditions leading to failures (see bug 11783 for an example).
-    // TODO: Remove the Torbutton menu entry again once we have done our
-    // security control redesign.
-    document.getElementById("menu_newIdentity").disabled = true;
-    document.getElementById("appMenuNewIdentity").disabled = true;
+    if (newIdentityInProgress) {
+      return;
+    }
+
+    newIdentityInProgress = true;
 
     let shouldConfirm =  m_tb_prefs.getBoolPref("extensions.torbutton.confirm_newnym");
 
@@ -789,14 +792,9 @@ torbutton_new_identity = async function() {
 
       if (confirmed) {
         await torbutton_do_new_identity();
-      } else {
-        // TODO: Remove the Torbutton menu entry again once we have done our
-        // security control redesign.
-        document.getElementById("menu_newIdentity").disabled = false;
-        document.getElementById("appMenuNewIdentity").disabled = false;
       }
     } else {
-        await torbutton_do_new_identity();
+      await torbutton_do_new_identity();
     }
   } catch(e) {
     // If something went wrong make sure we have the New Identity button
@@ -805,8 +803,8 @@ torbutton_new_identity = async function() {
     // security control redesign.
     torbutton_log(5, "Unexpected error on new identity: " + e);
     window.alert("Torbutton: Unexpected error on new identity: " + e);
-    document.getElementById("menu_newIdentity").disabled = false;
-    document.getElementById("appMenuNewIdentity").disabled = false;
+  } finally {
+    newIdentityInProgress = false;
   }
 }