code: function(auditRuleName, selectors) {
          if (!(auditRuleName in this.rules_))
              this.rules_[auditRuleName] = {};
          if (!('ignore' in this.rules_[auditRuleName]))
              this.rules_[auditRuleName].ignore = [];
          Array.prototype.push.call(this.rules_[auditRuleName].ignore, selectors);
      }
docs: Add the given selectors to the ignore list for the given audit rule.
  @param {string} auditRuleName The name of the audit rule
  @param {Array.<string>} selectors Query selectors to match nodes to
  ignore