onerror handler

onerror.js

(function() {
    var oldErrorHandler = window.onerror;
    window.onerror = function(errorMsg, file, line) {
        var e = encodeURIComponent;
        if (oldErrorHandler) {
            oldErrorHandler(errorMsg, file, line);
        }
        (new Image()).src = '/njl/log?msg=' + e(errorMsg) + '&level=error' + '&context[file]=' + e(file) + '&context[line]=' + e(line) + '&context[browser]=' + e(navigator.userAgent) + '&context[page]=' + e(document.location.href);
    };
})();