Fix first-run page in Opera

lib/utils.js

 /*
  * This file is part of Adblock Plus <http://adblockplus.org/>,
  * Copyright (C) 2006-2013 Eyeo GmbH
  *
  * Adblock Plus is free software: you can redistribute it and/or modify
  * it under the terms of the GNU General Public License version 3 as
  * published by the Free Software Foundation.
  *
  * Adblock Plus is distributed in the hope that it will be useful,
  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  * GNU General Public License for more details.
  *
  * You should have received a copy of the GNU General Public License
  * along with Adblock Plus.  If not, see <http://www.gnu.org/licenses/>.
  */
 
+let runAsyncQueue;
+
 var Utils = exports.Utils = {
   systemPrincipal: null,
   getString: function(id)
   {
     return id;
   },
+
   runAsync: function(callback, thisPtr)

[Thomas Greiner, 2013/10/16 13:36:46]

thisPtr is only implicitly used by callback.bind.apply which is non-obvious.
Therefore the variable itself is not necessary.

My personal preference here is to document that the second parameter is expected
to be a pointer rather than declaring a placeholder variable which is not used
inside the function. AFAIK we don't have any guidelines for this case though.

[Wladimir Palant, 2013/10/16 13:44:41]

That's mainly because this isn't the canonical implementation of that function -
it's rather an emulation of a function available in Firefox. Still, I removed
the parameter and added a comment instead.

   {
-    var params = Array.prototype.slice.call(arguments, 2);
-    window.setTimeout(function()
+    callback = callback.bind.apply(callback, Array.prototype.slice.call(arguments, 1));
+
+    if (typeof runAsyncQueue == "undefined")
     {
-      callback.apply(thisPtr, params);
-    }, 0);
+      runAsyncQueue = (document.readyState == "loading" ? [] : null)

[Thomas Greiner, 2013/10/16 13:36:46]

Nit: Semicolon at the end is missing.

[Wladimir Palant, 2013/10/16 13:44:41]

Done.

+      if (runAsyncQueue)
+      {
+        // Hack: Opera will happily run asynchronous actions while scripts are
+        // loading, queue them until the document is ready.
+        let loadHandler = function()
+        {
+          document.removeEventListener("DOMContentLoaded", loadHandler, false);
+
+          let queue = runAsyncQueue;
+          runAsyncQueue = null;
+          for each (let callback in queue)
+          {
+            try
+            {
+              callback();
+            }
+            catch(e)
+            {
+              Cu.reportError(e);
+            }
+          }
+        };
+        document.addEventListener("DOMContentLoaded", loadHandler, false);
+      }
+    }
+
+    if (runAsyncQueue)
+      runAsyncQueue.push(callback);
+    else
+      window.setTimeout(callback, 0);
   },
   get appLocale()
   {
     var locale = chrome.i18n.getMessage("@@ui_locale").replace(/_/g, "-");
     this.__defineGetter__("appLocale", function() {return locale});
     return this.appLocale;
   },
   generateChecksum: function(lines)
   {
     // We cannot calculate MD5 checksums yet :-(
@@ skipping 56 matching lines @@
     return selectedItem;
   },
 
   getDocLink: function(linkID)
   {
     var Prefs = require("prefs").Prefs;
     var docLink = Prefs.documentation_link;
     return docLink.replace(/%LINK%/g, linkID).replace(/%LANG%/g, Utils.appLocale);
   }
 };