Source
factory HashChangeEvent(String type, {bool canBubble: true, bool cancelable: true, String oldUrl, String newUrl}) { var options = { 'canBubble': canBubble, 'cancelable': cancelable, 'oldURL': oldUrl, 'newURL': newUrl, }; return JS('HashChangeEvent', 'new HashChangeEvent(#, #)', type, convertDartToNative_Dictionary(options)); }