Returns translated error message, called from AdminRewrite when an unsucsessful save has been made. A valid $code is anything that $this->saveActiveRules would return if an error occurs.
This function is called when new rules are saved and by rewrite.AdminRewrite to know if this rule should be displayed. If the parser overrides this function it needs to call this (the parent). It also verifies that locked rules are saved with the original pattern. We perform a sanity check to minimize possible conflicts and bad regular expressions.
Saves the active rewrite rules. This needs to be implemented by the specific plugin. It needs to save two rewrite params, activeRules and shortUrls. activeRules is just a serialized array of the given activeRules and shortUrls is returned by RewriteHelper::parseActiveRules(). It returns REWRITE_STATUS_OK on success.