Generate and use cross frame wrappers for types in other frames/windows.

tests/html/inner_frame_test.dart

 #library('InnerFrameTest');
 #import('../../lib/unittest/unittest.dart');
 #import('../../lib/unittest/html_config.dart');
 #import('dart:html');
 
 main() {
   if (window != window.top) {
     // Child frame.
 
     // The child's frame should not be able to access its parent's
     // document.
 
     // Check window.frameElement.
     try {
       var parentDocument = window.frameElement.document;
       var div = parentDocument.$dom_createElement("div");
       div.id = "illegalFrameElement";
       parentDocument.body.nodes.add(div);
       Expect.fail('Should not reach here.');
     } catch (NoSuchMethodException e) {
+      // TODO(vsm): This should be UnsupportedOperationException.

[sra1, 2012/05/10 00:12:06]

Do you think it is worth catching both exceptions?

       // Expected.
     }
 
     // Check window.top.
     try {
       final top = window.top;
       var parentDocument = top.document;
       var div = parentDocument.$dom_createElement("div");
       div.id = "illegalTop";
       parentDocument.body.nodes.add(div);
       Expect.fail('Should not reach here.');
-    } catch (var e) {
+    } catch (NoSuchMethodException e) {
+      // TODO(vsm): This should be UnsupportedOperationException.
       // Expected.
-      // TODO(vsm): Enforce this is a NoSuchMethodException.
     }
+
+    // Install Message Handler.
+    window.on.message.add((e) {
+        if (e.data == 'test1') {
+          window.parent.postMessage('test2', '*');
+        }
+      });
     return;
   }
 
   // Parent / test frame
   useHtmlConfiguration();
 
   final iframe = new Element.tag('iframe');
   iframe.src = window.location.href;
 
   asyncTest('prepare', 1, () {
       iframe.on.load.add((e) => callbackDone());
       document.body.nodes.add(iframe);
     });
 
+  asyncTest('postMessage', 1, () {
+      window.on.message.add((e) {
+          if (e.data == 'test2') {
+            // Ensure that equality is implemented in cross frame
+            // wrapper.
+            Expect.equals(iframe.contentWindow, e.source);
+            callbackDone();
+          }
+        });
+      iframe.contentWindow.postMessage('test1', '*');
+    });
+
   test('frameElement', () {
       var div = document.query('#illegalFrameElement');
 
       // Ensure that this parent frame was not modified by its child.
       Expect.isNull(div);
     });
 
   test('top', () {
       var div = document.query('#illegalTop');
 
       // Ensure that this parent frame was not modified by its child.
       Expect.isNull(div);
     });
 }