"Reverting 23366"

tools/dom/templates/html/impl/impl_Element.darttemplate

Index: tools/dom/templates/html/impl/impl_Element.darttemplate
diff --git a/tools/dom/templates/html/impl/impl_Element.darttemplate b/tools/dom/templates/html/impl/impl_Element.darttemplate
index 7a9f12efbb14ada6e90c08fac99e5b7e2542dcda..188759ea742f09c3ae992fe2279559f0bc12dab9 100644
--- a/tools/dom/templates/html/impl/impl_Element.darttemplate
+++ b/tools/dom/templates/html/impl/impl_Element.darttemplate
@@ -58,24 +58,6 @@ class _ChildrenElementList extends ListBase<Element> {
     throw new UnsupportedError('Cannot sort element lists');
   }
 
-  void removeWhere(bool test(Element element)) {
-    _filter(test, false);
-  }
-
-  void retainWhere(bool test(Element element)) {
-    _filter(test, true);
-  }
-
-  void _filter(bool test(var element), bool retainMatching) {
-    List removed = [];
-    if (retainMatching) {
-      removed = _element.children.where((e) => !test(e));
-    } else {
-      removed = _element.children.where(test);
-    }
-    for (var e in removed) e.remove();
-  }
-
   void setRange(int start, int end, Iterable<Element> iterable,
                 [int skipCount = 0]) {
     throw new UnimplementedError();