Refined types for most HtmlElement factory constructors

sdk/lib/svg/dart2js/svg_dart2js.dart

Index: sdk/lib/svg/dart2js/svg_dart2js.dart
diff --git a/sdk/lib/svg/dart2js/svg_dart2js.dart b/sdk/lib/svg/dart2js/svg_dart2js.dart
index e15ec4f7d7458598035b46612adcd4dd80fdf01a..558ffbd928f538c6a806aa04765c90d723d58e58 100644
--- a/sdk/lib/svg/dart2js/svg_dart2js.dart
+++ b/sdk/lib/svg/dart2js/svg_dart2js.dart
@@ -4722,14 +4722,14 @@ class SvgElement extends Element implements GlobalEventHandlers {
   }
 
   String get outerHtml {
-    final container = new Element.tag("div");
+    final container = new DivElement();
     final SvgElement cloned = this.clone(true);
     container.children.add(cloned);
     return container.innerHtml;
   }
 
   String get innerHtml {
-    final container = new Element.tag("div");
+    final container = new DivElement();
     final SvgElement cloned = this.clone(true);
     container.children.addAll(cloned.children);
     return container.innerHtml;