Fixes for Element API changes

pkg/custom_element/lib/custom_element.dart

 // Copyright (c) 2013, the Dart project authors.  Please see the AUTHORS file
 // for details. All rights reserved. Use of this source code is governed by a
 // BSD-style license that can be found in the LICENSE file.
 
 /**
  * Custom Elements let authors define their own elements. Authors associate code
  * with custom tag names, and then use those custom tag names as they would any
  * standard tag. See <www.polymer-project.org/platform/custom-elements.html>
  * for more information.
  */
@@ skipping 295 matching lines @@
 
   void set innerHTML(String v) {
     host.innerHtml = v;
   }
 
   String get innerHtml => host.innerHtml;
   void set innerHtml(String v) {
     host.innerHtml = v;
   }
 
+  InputMethodContext get inputMethodContext => host.inputMethodContext;
+
   bool get isContentEditable => host.isContentEditable;
 
   String get lang => host.lang;
   set lang(String v) { host.lang = v; }
 
   String get outerHtml => host.outerHtml;
 
   bool get spellcheck => host.spellcheck;
   set spellcheck(bool v) { host.spellcheck = v; }
 
   int get tabIndex => host.tabIndex;
   set tabIndex(int i) { host.tabIndex = i; }
 
   String get title => host.title;
 
   set title(String value) { host.title = value; }
 
   bool get translate => host.translate;
   set translate(bool v) { host.translate = v; }
 
   String get dropzone => host.dropzone;
   set dropzone(String v) { host.dropzone = v; }
 
   void click() { host.click(); }
 
-  InputMethodContext getInputContext() => host.getInputContext();
+  List<Node> getDestinationInsertionPoints() =>
+    host.getDestinationInsertionPoints();
 
   Element insertAdjacentElement(String where, Element element) =>
     host.insertAdjacentElement(where, element);
 
   void insertAdjacentHtml(String where, String html) {
     host.insertAdjacentHtml(where, html);
   }
 
   void insertAdjacentText(String where, String text) {
     host.insertAdjacentText(where, text);
@@ skipping 307 matching lines @@
       for (var removed in record.removedNodes) {
         if (identical(node, removed)) {
           observer.disconnect();
           element.removed();
           return;
         }
       }
     }
   }).observe(element.parentNode, childList: true);
 }