code: function() {
          // Initialize category filters
          this._categoryFilters = [];
          var aInitialCategories = Logger.categories;
  
          for(var j=0; j < aInitialCategories.length; j++) {
              var sCategory = aInitialCategories[j];
  
              // Add category to the internal array of filters
              this._categoryFilters.push(sCategory);
  
              // Add checkbox element if UI is enabled
              if(this._elCategoryFilters) {
                  this._createCategoryCheckbox(sCategory);
              }
          }
      }
docs: Initializes category filters.
  
  @method _initCategories
  @private