dart2js_html: Fix for issue 29538 - some returned lists may be null

sdk/lib/svg/dart2js/svg_dart2js.dart

 /**
  * Scalable Vector Graphics:
  * Two-dimensional vector graphics with support for events and animation.
  *
  * For details about the features and syntax of SVG, a W3C standard,
  * refer to the
  * [Scalable Vector Graphics Specification](http://www.w3.org/TR/SVG/).
  */
 library dart.dom.svg;
 
@@ skipping 5778 matching lines @@
   @DomName('SVGSVGElement.getCurrentTime')
   @DocsEditable()
   double getCurrentTime() native;
 
   @DomName('SVGSVGElement.getElementById')
   @DocsEditable()
   Element getElementById(String elementId) native;
 
   @DomName('SVGSVGElement.getEnclosureList')
   @DocsEditable()
-  @Returns('NodeList')
+  @Returns('NodeList|Null')
   @Creates('NodeList')
   List<Node> getEnclosureList(Rect rect, SvgElement referenceElement) native;
 
   @DomName('SVGSVGElement.getIntersectionList')
   @DocsEditable()
-  @Returns('NodeList')
+  @Returns('NodeList|Null')
   @Creates('NodeList')
   List<Node> getIntersectionList(Rect rect, SvgElement referenceElement) native;
 
   @DomName('SVGSVGElement.pauseAnimations')
   @DocsEditable()
   void pauseAnimations() native;
 
   @DomName('SVGSVGElement.setCurrentTime')
   @DocsEditable()
   void setCurrentTime(num seconds) native;
@@ skipping 959 matching lines @@
   /**
    * Constructor instantiated by the DOM when a custom element has been created.
    *
    * This can only be called by subclasses from their created constructor.
    */
   _SVGMPathElement.created() : super.created();
 
   // From SVGURIReference
 
 }