fix filter setting/unsetting. the input value has to be manually set/unset when adding/removing filters.

assets/javascripts/reporting/filters.js

@@ -44,13 +44,15 @@ Reporting.Filters = {
     var field_el = $('tr_' +  field);
     if (field_el !== null) {
       // the following command might be included into the callback_function (which is called after the ajax request) later
-      $('rm_' + field).value = field;
       var display_functor;
       if (options.show_filter) {
         display_functor = options.slowly ? Effect.Appear : Element.show;
         Reporting.Filters.load_available_values_for_filter(field, options.callback_func);
+        $('rm_' + field).value = field; // set the value, so the serialized form will return this filter
       } else {
         display_functor = options.slowly ? Effect.Fade : Element.hide;
+        field_el.removeAttribute('data-selected');
+        $('rm_' + field).value = ""; // reset the value, so the serialized form will not return this filter
       }
       display_functor(field_el);
       Reporting.Filters.operator_changed(field, $("operators_" + field));