Copy lib/dom tests that use dart:html to lib/html.

tests/dom/events_test.dart

-#library('EventsTest');
-#import('../../lib/unittest/unittest.dart');
-#import('../../lib/unittest/html_config.dart');
-#import('dart:html');
-
-main() {
-  useHtmlConfiguration();
-  test('TimeStamp', () {
-    Event event = new Event('test');
-
-    int timeStamp = event.timeStamp;
-    Expect.isTrue(timeStamp > 0);
-  });
-  // The next test is not asynchronous because [on['test'].dispatch(event)] fires the event
-  // and event listener synchronously.
-  test('EventTarget', () {
-    Element element = new Element.tag('test');
-    element.id = 'eventtarget';
-    window.document.body.nodes.add(element);
-
-    int invocationCounter = 0;
-    void handler(Event e) {
-      Expect.equals('test', e.type);
-      Element target = e.target;
-      Expect.identical(element, target);
-      invocationCounter++;
-    }
-
-    Event event = new Event('test');
-
-    invocationCounter = 0;
-    element.on['test'].dispatch(event);
-    Expect.equals(0, invocationCounter);
-
-    element.on['test'].add(handler, false);
-    invocationCounter = 0;
-    element.on['test'].dispatch(event);
-    Expect.equals(1, invocationCounter);
-
-    element.on['test'].remove(handler, false);
-    invocationCounter = 0;
-    element.on['test'].dispatch(event);
-    Expect.equals(0, invocationCounter);
-
-    element.on['test'].add(handler, false);
-    invocationCounter = 0;
-    element.on['test'].dispatch(event);
-    Expect.equals(1, invocationCounter);
-
-    element.on['test'].add(handler, false);
-    invocationCounter = 0;
-    element.on['test'].dispatch(event);
-    Expect.equals(1, invocationCounter);
-  });
-  test('InitMouseEvent', () {
-    DivElement div = new Element.tag('div');
-    MouseEvent event = document.$dom_createEvent('MouseEvent');
-    event.$dom_initMouseEvent('zebra', true, true, window, 0, 1, 2, 3, 4, false, false, false, false, 0, div);
-  });
-}