Issue #430 - Filter hit counters aren't cleared

lib/filterListener.js

 /*
  * This file is part of Adblock Plus <http://adblockplus.org/>,
  * Copyright (C) 2006-2014 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 28 matching lines @@
 /**
  * Increases on filter changes, filters will be saved if it exceeds 1.
  * @type Integer
  */
 let isDirty = 0;
 
 /**
  * This object can be used to change properties of the filter change listeners.
  * @class
  */
-let FilterListener = exports.FilterListener =
+let FilterListener =
 {
   /**
    * Set to true when executing many changes, changes will only be fully applied after this variable is set to false again.
    * @type Boolean
    */
   get batchMode()
   {
     return batchMode;
   },
   set batchMode(value)
@@ skipping 168 matching lines @@
   }
 
   flushElemHide();
 }
 
 /**
  * Filter change listener
  */
 function onFilterChange(action, filter, newValue, oldValue)
 {
-  if (action == "hitCount" || action == "lastHit")
+  if (action == "hitCount" && newValue == 0)
+  {
+    // Filter hits are being reset, make sure these changes are saved.
+    FilterListener.setDirty(0);
+  }
+  else if (action == "hitCount" || action == "lastHit")
     FilterListener.setDirty(0.002);
   else
     FilterListener.setDirty(1);
 
   if (action != "added" && action != "removed" && action != "disabled")
     return;
 
   if ((action == "added" || action == "removed") && filter.disabled)
   {
     // Ignore adding/removing of disabled filters
@@ skipping 19 matching lines @@
     defaultMatcher.clear();
     ElemHide.clear();
     for (let subscription of FilterStorage.subscriptions)
       if (!subscription.disabled)
         subscription.filters.forEach(addFilter);
     flushElemHide();
   }
   else if (action == "save")
     isDirty = 0;
 }