Fix dartium tests after legacy getter removal

sdk/lib/html/src/native_DOMImplementation.dart

Index: sdk/lib/html/src/native_DOMImplementation.dart
===================================================================
--- sdk/lib/html/src/native_DOMImplementation.dart	(revision 15525)
+++ sdk/lib/html/src/native_DOMImplementation.dart	(working copy)
@@ -51,13 +51,13 @@
   _DOMWindowCrossFrame.internal();
 
   // Fields.
-  History get history() native "DOMWindow_history_cross_frame_Getter";
-  Location get location() native "DOMWindow_location_cross_frame_Getter";
-  bool get closed() native "DOMWindow_closed_Getter";
-  int get length() native "DOMWindow_length_Getter";
-  Window get opener() native "DOMWindow_opener_Getter";
-  Window get parent() native "DOMWindow_parent_Getter";
-  Window get top() native "DOMWindow_top_Getter";
+  History get history native "DOMWindow_history_cross_frame_Getter";
+  Location get location native "DOMWindow_location_cross_frame_Getter";
+  bool get closed native "DOMWindow_closed_Getter";
+  int get length native "DOMWindow_length_Getter";
+  Window get opener native "DOMWindow_opener_Getter";
+  Window get parent native "DOMWindow_parent_Getter";
+  Window get top native "DOMWindow_top_Getter";
 
   // Methods.
   void close() native "DOMWindow_close_Callback";