Exposing DOM float & double types as double rather than num.

tests/html/css_test.dart

Index: tests/html/css_test.dart
diff --git a/tests/html/css_test.dart b/tests/html/css_test.dart
index 01a05d06b8e7a460a770db0e9ea6e442d20541d9..4dbc8b0dcbc549ff577310eaf1fd1c97ab668b8a 100644
--- a/tests/html/css_test.dart
+++ b/tests/html/css_test.dart
@@ -30,10 +30,10 @@ main() {
           ''';
         document.body.append(element);
 
-        Point point = new Point(5, 2);
+        Point point = new Point(5.0, 2.0);
         checkPoint(5, 2, point);
         checkPoint(255, 102, window.convertPointFromNodeToPage(element, point));
-        point = new Point(5, 100);
+        point = new Point(5.0, 100.0);
         checkPoint(5, 100, point);
         checkPoint(255, 200, window.convertPointFromNodeToPage(element, point));
       }, expectation);