Run dart2js tests unmodified in browser.

dart/pkg/unittest/test_controller.js

 // Copyright (c) 2011, the Dart project authors.  Please see the AUTHORS file
 // for details. All rights reserved. Use of this source code is governed by a
 // BSD-style license that can be found in the LICENSE file.
 
 /**
  * Test controller logic - used by unit test harness to embed tests in
  * DumpRenderTree.
  */
 
 if (navigator.webkitStartDart) {
@@ skipping 57 matching lines @@
     // A window.postMessage might have been enqueued after this timeout.
     // Just sleep another time to give the browser the time to process the
     // posted message.
     setTimeout(function() {
       if (testRunner && !testRunner.startedDartTest) {
         testRunner.notifyDone();
       }
     }, 0);
   }, 50);
 };
+
+function dartMainRunner(main) {
+  var caughtError;
+  function handleError(e) { caughtError = e; }
+
+  window.postMessage('unittest-suite-wait-for-done', '*');
+  window.addEventListener('error', handleError, false);
+  main();

[kasperl, 2012/09/06 10:29:29]

We have had issues with uncaught JavaScript exceptions falling out of main which
leads to tests that time out. Maybe this would be a great time to wrap the
main() call in try-catch?

[ahe, 2012/09/08 13:32:32]

I think that is handled by 'window.addEventListener("error",...' above.

+  window.removeEventListener('error', handleError, false);
+  if (typeof caughtError != 'undefined') {
+    document.body.innerHTML = String(caughtError);
+  } else {
+    document.body.innerHTML = "PASS";
+  }
+  window.postMessage('unittest-suite-done', '*');
+}