Proper support for throwing not implemented.

client/dom/src/native_DOMImplementation.dart

Index: client/dom/src/native_DOMImplementation.dart
diff --git a/client/dom/src/native_DOMImplementation.dart b/client/dom/src/native_DOMImplementation.dart
index 4dd9eb6a146fbc8f143b75685736eb1c9b500c34..611266e4c4a241c77c5725d32843a007d20670a0 100644
--- a/client/dom/src/native_DOMImplementation.dart
+++ b/client/dom/src/native_DOMImplementation.dart
@@ -11,8 +11,8 @@ class Utils {
     return result;
   }
 
-  static makeNotImplementedException() {
-    return const NotImplementedException();
+  static makeNotImplementedException(String fileName, int lineNo) {
+    return new UnsupportedOperationException('[info: $fileName:$lineNo]');
   }
 
   static window() native "Utils_window";