How to use the uglify-js-papandreou.AST_SymbolRef function in uglify-js-papandreou

}, this);
                }
            }, this);

            // Detect global 'use strict' directives
            if (parentNode === this.parseTree &&
                node instanceof uglifyJs.AST_Directive &&
                node.value === 'use strict') {
                this.strict = true;
            }

            if (node instanceof uglifyJs.AST_SimpleStatement &&
                node.body instanceof uglifyJs.AST_Call &&
                node.body.expression instanceof uglifyJs.AST_Dot &&
                node.body.expression.property === 'config' &&
                node.body.expression.expression instanceof uglifyJs.AST_SymbolRef &&
                node.body.args[0] instanceof uglifyJs.AST_Object &&
                (node.body.expression.expression.name === 'require' || node.body.expression.expression.name === 'requirejs')) {

                outgoingRelations.push(new AssetGraph.JavaScriptRequireJsConfig({
                    from: this,
                    node: node.body.args[0],
                    parentNode: node.body,
                    to: new AssetGraph.RequireJsConfig({
                        parseTree: node.body.args[0].transform(deepCloneTransform)
                    })
                }));
            } else if (node instanceof uglifyJs.AST_Var) {
                node.definitions.forEach(function (varDefNode) {
                    if (varDefNode.name.name === 'require' && varDefNode.value instanceof uglifyJs.AST_Object) {
                        outgoingRelations.push(new AssetGraph.JavaScriptRequireJsConfig({
                            isRequireVar: true,

if (varDefNode.name.name === 'require' && varDefNode.value instanceof uglifyJs.AST_Object) {
                        outgoingRelations.push(new AssetGraph.JavaScriptRequireJsConfig({
                            isRequireVar: true,
                            from: this,
                            parentNode: varDefNode,
                            node: varDefNode.value,
                            to: new AssetGraph.RequireJsConfig({
                                parseTree: varDefNode.value.transform(deepCloneTransform)
                            })
                        }));
                    }
                }, this);
            } else if (node instanceof uglifyJs.AST_Call) {
                var parentParentNode = stack[stack.length - 3];
                if (node.expression instanceof uglifyJs.AST_Dot && node.expression.property === 'module' &&
                    node.expression.expression instanceof uglifyJs.AST_SymbolRef &&
                    node.expression.expression.name === 'angular') {

                    var diveIntoAngularMethodCall = function (argumentNodes, templateCacheVariableName) {
                        var angularWalker = new uglifyJs.TreeWalker(function (node) {
                            var parentNode = angularWalker.parent();
                            if (node instanceof uglifyJs.AST_Object) {
                                node.properties.forEach(function (keyValue) {
                                    if (keyValue.key === 'templateUrl' && keyValue.value instanceof uglifyJs.AST_String) {
                                        outgoingRelations.push(new AssetGraph.JavaScriptAngularJsTemplate({
                                            from: this,
                                            to: {
                                                type: 'Html',
                                                url: keyValue.value.value
                                            },
                                            node: keyValue,
                                            parentNode: node