adblockplusopera: Port UI code from Chrome

background.js

 var DownloadableSubscription = require("subscriptionClasses").DownloadableSubscription;
 var WhitelistFilter = require("filterClasses").WhitelistFilter;
 var FilterNotifier = require("filterNotifier").FilterNotifier;
 var FilterStorage = require("filterStorage").FilterStorage;
 var Prefs = require("prefs").Prefs;
 var Synchronizer = require("synchronizer").Synchronizer;
 var Subscription = require("subscriptionClasses").Subscription;
 var SpecialSubscription = require("subscriptionClasses").SpecialSubscription;
 var Utils = require("utils").Utils;
 
@@ skipping 170 matching lines @@
     toolbar.addItem(toolbarButton);
   else
     toolbar.removeItem(toolbarButton);
 }
 
 function getJson(url)
 {
   var request = new XMLHttpRequest();
   request.open("GET", url, false);
   request.responseType = "json";
   request.send();

[Wladimir Palant, 2012/10/19 15:47:41]

There is still a potential unhandled exception here :-(
I just tested and a synchronous XMLHttpRequest will throw an exception on
request.send() if a non-existent file is requested. It will *not* complete but
leave request.response uninitialized.

[Felix Dahlke, 2012/10/19 16:07:27]

Yes, it will return an undefined value. My first approach was to check for
exceptions here but I couldn't differentiate between "could not load" and "could
not parse" when the file is loaded locally, so I decided to just return
undefined in case of error, and handle the general case in loadI18nMessages(). I
did test this, just tested it again. Works fine. Would you prefer if I threw an
Error here instead of returning undefined?

[Wladimir Palant, 2012/10/22 08:57:51]

Ok, it seems that the widget:// protocol behaves differently from file:// here -
my bad. I verified that the fallback works correctly if the locale doesn't
exist.

   return request.response;
 }
 
 function loadMessagesForLocale(locale)
 {
   var messagesFileName = "messages.json";
   var messagesPath;
   if (locale)
     messagesPath = "locales/" + locale + "/" + messagesFileName;
   else
     messagesPath = messagesFileName;
 
   var messages = getJson(messagesPath);
   if (!messages)
   {
     console.error("Failed to load messages for locale "
                   + (locale ? locale : "default"));
     return;
   }
 
   for (var i in messages)
     i18nMessages[i] = messages[i];
 }
 
 function loadI18nMessages()
 {
-  i18nMessages = {};
-
   // Could be parsed from config.xml
   var defaultLocale = "en";
 
-  if (locale !== defaultLocale)

[Wladimir Palant, 2012/10/19 15:47:41]

I'm not really happy with the hack you use to define the locale variable. How
about just loading the fallback each time? It won't do any harm if the locale is
already "en" but it will make the code simpler and remove reliance on
assumptions about how Opera's locale selection mechanism works.

[Felix Dahlke, 2012/10/19 16:07:27]

Done. It's not necessary anymore and I'm frankly happy to get rid of that hack,
which was apparently only necessary for OS X anyway.

-    loadMessagesForLocale(defaultLocale);
-
+  i18nMessages = {};
+  loadMessagesForLocale(defaultLocale);
   loadMessagesForLocale();
 }
 
 setDefaultOptions();
 createToolbarButton();
 refreshToolbarButton();
 loadI18nMessages();