This issue was originally filed by LukeEC...@gmail.com

Source code:

// Go ahead and modify this example.

var greeting = "Hello, World!";

// Prints a greeting.
void main() {
  // The [print] function displays a message in the "Console" box.
  // Try modifying the greeting above and watch the "Console" box change.
  print(greeting);
}
Error and stack trace:

INTERNAL ERROR
We would appreciate if you take a moment to report this at https://code.google.com/p/dart/issues/entry?template=Try+Dart+Internal+ErrorError and stack trace:
Internal Error: The library 'dart:_js_helper' does not contain required element: 'Native'., Error
    at dart.wrapException (http://try.dartlang.org/compiler_isolate.dart.js:2462:15)
    at Compiler0.internalError$2 (http://try.dartlang.org/compiler_isolate.dart.js:18828:15)
    at Compiler0.findRequiredElement$2 (http://try.dartlang.org/compiler_isolate.dart.js:18880:14)
    at _LibraryLoaderTask_processLibraryTags_closure0.call$1 (http://try.dartlang.org/compiler_isolate.dart.js:30035:39)
    at _RootZone.runUnary$2 (http://try.dartlang.org/compiler_isolate.dart.js:11166:18)
    at _Future__propagateToListeners_handleValueCallback.call$0 (http://try.dartlang.org/compiler_isolate.dart.js:9734:57)
    at dart._Future.static._Future__propagateToListeners (http://try.dartlang.org/compiler_isolate.dart.js:9628:131)
    at _Future._complete$1 (http://try.dartlang.org/compiler_isolate.dart.js:9471:11)
    at Future_doWhile_closure.call$1 (http://try.dartlang.org/compiler_isolate.dart.js:9370:12)
    at _RootZone.runUnaryGuarded$2 (http://try.dartlang.org/compiler_isolate.dart.js:11111:18)