Issue 2658 - Got rid of try..catch for filter validation

options.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
@@ skipping 453 matching lines @@
   var filterText = "@@||" + domain + "^$document";
   FilterStorage.addFilter(Filter.fromText(filterText));
 }
 
 // Adds filter text that user typed to the selection box
 function addTypedFilter(event)
 {
   event.preventDefault();
 
   var element = document.getElementById("newFilter");
-  var filter;
+  var result = parseFilter(element.value);
 
-  try
+  if (result.error)
   {
-    filter = parseFilter(element.value);
-  }
-  catch (error)
-  {
-    alert(error);
+    alert(result.error);
     return;
   }
 
-  if (filter)
-    FilterStorage.addFilter(filter);
+  if (result.filter)
+    FilterStorage.addFilter(result.filter);
 
   element.value = "";
 }
 
 // Removes currently selected whitelisted domains
 function removeSelectedExcludedDomain(event)
 {
   event.preventDefault();
   var excludedDomainsBox = document.getElementById("excludedDomainsBox");
   var remove = [];
@@ skipping 36 matching lines @@
     for (var i = 0; i < userFiltersBox.length; i++)
       text += userFiltersBox.options[i].value + "\n";
     document.getElementById("rawFiltersText").value = text;
   }
 }
 
 // Imports filters in the raw text box
 function importRawFiltersText()
 {
   var text = document.getElementById("rawFiltersText").value;
+  var result = parseFilters(text, true);
 
-  var add;
-  try
+  if (result.error)
   {
-    add = parseFilters(text, true);
-  }
-  catch (error)
-  {
-    alert(error);
+    alert(result.error);
     return;
   }
 
   var seenFilter = Object.create(null);
-  for (var i = 0; i < add.length; i++)
+  for (var i = 0; i < result.filters.length; i++)
   {
-    var filter = add[i];
+    var filter = result.filters[i];
     FilterStorage.addFilter(filter);
     seenFilter[filter.text] = null;
   }
 
   var remove = [];
   for (var i = 0; i < FilterStorage.subscriptions.length; i++)
   {
     var subscription = FilterStorage.subscriptions[i];
     if (!(subscription instanceof SpecialSubscription))
       continue;
@@ skipping 73 matching lines @@
       links[i].href = arguments[i + 1];
       links[i].setAttribute("target", "_blank");
     }
     else if (typeof arguments[i + 1] == "function")
     {
       links[i].href = "javascript:void(0);";
       links[i].addEventListener("click", arguments[i + 1], false);
     }
   }
 }