unittest step2: bye bye to multiple entrypoints for unittest

client/tests/client/dom/HiddenDom2Test.dart

Index: client/tests/client/dom/HiddenDom2Test.dart
diff --git a/client/tests/client/dom/HiddenDom2Test.dart b/client/tests/client/dom/HiddenDom2Test.dart
index 500ddcb38cc0aa8785db0edfc35980c88ad0f28f..1edc919d564911d14ebbd8bd19635295c5d8eb6e 100644
--- a/client/tests/client/dom/HiddenDom2Test.dart
+++ b/client/tests/client/dom/HiddenDom2Test.dart
@@ -1,12 +1,13 @@
 #library('HiddenDom2Test');
-#import('../../../../lib/unittest/unittest_html.dart');
+#import('../../../../lib/unittest/unittest.dart');
+#import('../../../../lib/unittest/html_config.dart');
 #import('dart:html');
 
 // Test that the dart:html API does not leak native jsdom methods:
 //   appendChild operation.
 
 main() {
-  forLayoutTests();
+  useHtmlConfiguration(isLayoutTest: true);
 
   test('test1', () {
     document.body.elements.add(new Element.html(@'''