Issue 370 - Make "Block element" hide elements for added filters

background.js

 /*
  * This file is part of Adblock Plus <https://adblockplus.org/>,
  * Copyright (C) 2006-2015 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/>.
  */
 
 with(require("filterClasses"))
 {
   this.Filter = Filter;
   this.BlockingFilter = BlockingFilter;
   this.WhitelistFilter = WhitelistFilter;
+  this.ElemHideFilter = ElemHideFilter;
 }
 with(require("subscriptionClasses"))
 {
   this.Subscription = Subscription;
   this.DownloadableSubscription = DownloadableSubscription;
   this.SpecialSubscription = SpecialSubscription;
 }
 with(require("whitelisting"))
 {
   this.isPageWhitelisted = isPageWhitelisted;
@@ skipping 494 matching lines @@
       try
       {
         filters = parseFilters(msg.text);
       }
       catch (error)
       {
         sendResponse({status: "invalid", error: error});
         break;
       }
 
+      var selectors = [];
       for (var i = 0; i < filters.length; i++)
-        FilterStorage.addFilter(filters[i]);
+      {
+        var filter = filters[i];
+        FilterStorage.addFilter(filter);
 
-      sendResponse({status: "ok"});
+        if (filter instanceof ElemHideFilter)
+          selectors.push(filter.selector);
+      }
+
+      sendResponse({status: "ok", selectors: selectors});
       break;
     case "add-subscription":
       ext.showOptions(function(page)
       {
         page.sendMessage(msg);
       });
       break;
     case "add-sitekey":
       processKey(msg.token, sender.page, sender.frame);
       break;
@@ skipping 36 matching lines @@
   page.sendMessage({type: "clickhide-deactivate"});
   refreshIconAndContextMenu(page);
 });
 
 setTimeout(function()
 {
   var notificationToShow = NotificationStorage.getNextToShow();
   if (notificationToShow)
     showNotification(notificationToShow);
 }, 3 * 60 * 1000);