Index: frontend/node_modules/stackframe/stackframe.js
===================================================================
--- frontend/node_modules/stackframe/stackframe.js	(revision 9af201e94b5a79beb92a30858fc54de4bc3b9449)
+++ frontend/node_modules/stackframe/stackframe.js	(revision 9af201e94b5a79beb92a30858fc54de4bc3b9449)
@@ -0,0 +1,143 @@
+(function(root, factory) {
+    'use strict';
+    // Universal Module Definition (UMD) to support AMD, CommonJS/Node.js, Rhino, and browsers.
+
+    /* istanbul ignore next */
+    if (typeof define === 'function' && define.amd) {
+        define('stackframe', [], factory);
+    } else if (typeof exports === 'object') {
+        module.exports = factory();
+    } else {
+        root.StackFrame = factory();
+    }
+}(this, function() {
+    'use strict';
+    function _isNumber(n) {
+        return !isNaN(parseFloat(n)) && isFinite(n);
+    }
+
+    function _capitalize(str) {
+        return str.charAt(0).toUpperCase() + str.substring(1);
+    }
+
+    function _getter(p) {
+        return function() {
+            return this[p];
+        };
+    }
+
+    var booleanProps = ['isConstructor', 'isEval', 'isNative', 'isToplevel'];
+    var numericProps = ['columnNumber', 'lineNumber'];
+    var stringProps = ['fileName', 'functionName', 'source'];
+    var arrayProps = ['args'];
+    var objectProps = ['evalOrigin'];
+
+    var props = booleanProps.concat(numericProps, stringProps, arrayProps, objectProps);
+
+    function StackFrame(obj) {
+        if (!obj) return;
+        for (var i = 0; i < props.length; i++) {
+            if (obj[props[i]] !== undefined) {
+                this['set' + _capitalize(props[i])](obj[props[i]]);
+            }
+        }
+    }
+
+    StackFrame.prototype = {
+        getArgs: function() {
+            return this.args;
+        },
+        setArgs: function(v) {
+            if (Object.prototype.toString.call(v) !== '[object Array]') {
+                throw new TypeError('Args must be an Array');
+            }
+            this.args = v;
+        },
+
+        getEvalOrigin: function() {
+            return this.evalOrigin;
+        },
+        setEvalOrigin: function(v) {
+            if (v instanceof StackFrame) {
+                this.evalOrigin = v;
+            } else if (v instanceof Object) {
+                this.evalOrigin = new StackFrame(v);
+            } else {
+                throw new TypeError('Eval Origin must be an Object or StackFrame');
+            }
+        },
+
+        toString: function() {
+            var fileName = this.getFileName() || '';
+            var lineNumber = this.getLineNumber() || '';
+            var columnNumber = this.getColumnNumber() || '';
+            var functionName = this.getFunctionName() || '';
+            if (this.getIsEval()) {
+                if (fileName) {
+                    return '[eval] (' + fileName + ':' + lineNumber + ':' + columnNumber + ')';
+                }
+                return '[eval]:' + lineNumber + ':' + columnNumber;
+            }
+            if (functionName) {
+                return functionName + ' (' + fileName + ':' + lineNumber + ':' + columnNumber + ')';
+            }
+            return fileName + ':' + lineNumber + ':' + columnNumber;
+        }
+    };
+
+    StackFrame.fromString = function StackFrame$$fromString(str) {
+        var argsStartIndex = str.indexOf('(');
+        var argsEndIndex = str.lastIndexOf(')');
+
+        var functionName = str.substring(0, argsStartIndex);
+        var args = str.substring(argsStartIndex + 1, argsEndIndex).split(',');
+        var locationString = str.substring(argsEndIndex + 1);
+
+        if (locationString.indexOf('@') === 0) {
+            var parts = /@(.+?)(?::(\d+))?(?::(\d+))?$/.exec(locationString, '');
+            var fileName = parts[1];
+            var lineNumber = parts[2];
+            var columnNumber = parts[3];
+        }
+
+        return new StackFrame({
+            functionName: functionName,
+            args: args || undefined,
+            fileName: fileName,
+            lineNumber: lineNumber || undefined,
+            columnNumber: columnNumber || undefined
+        });
+    };
+
+    for (var i = 0; i < booleanProps.length; i++) {
+        StackFrame.prototype['get' + _capitalize(booleanProps[i])] = _getter(booleanProps[i]);
+        StackFrame.prototype['set' + _capitalize(booleanProps[i])] = (function(p) {
+            return function(v) {
+                this[p] = Boolean(v);
+            };
+        })(booleanProps[i]);
+    }
+
+    for (var j = 0; j < numericProps.length; j++) {
+        StackFrame.prototype['get' + _capitalize(numericProps[j])] = _getter(numericProps[j]);
+        StackFrame.prototype['set' + _capitalize(numericProps[j])] = (function(p) {
+            return function(v) {
+                if (!_isNumber(v)) {
+                    throw new TypeError(p + ' must be a Number');
+                }
+                this[p] = Number(v);
+            };
+        })(numericProps[j]);
+    }
+
+    for (var k = 0; k < stringProps.length; k++) {
+        StackFrame.prototype['get' + _capitalize(stringProps[k])] = _getter(stringProps[k]);
+        StackFrame.prototype['set' + _capitalize(stringProps[k])] = (function(p) {
+            return function(v) {
+                this[p] = String(v);
+            };
+        })(stringProps[k]);
+    }
+
+    return StackFrame;
+}));