fix ClassTypeAlias extends

lib/runtime/dart/_internal.js

 var _internal;
 (function(exports) {
   'use strict';
   class EfficientLength extends core.Object {}
   let ListIterable$ = dart.generic(function(E) {
     class ListIterable extends collection.IterableBase$(E) {
       ListIterable() {
         super.IterableBase();
       }
       get [core.$iterator]() {
@@ skipping 1365 matching lines @@
         if (fillValue === void 0)
           fillValue = null;
         throw new core.UnsupportedError("Cannot modify an unmodifiable list");
       }
     }
     UnmodifiableListMixin[dart.implements] = () => [core.List$(E)];
     return UnmodifiableListMixin;
   });
   let UnmodifiableListMixin = UnmodifiableListMixin$();
   let FixedLengthListBase$ = dart.generic(function(E) {
-    class FixedLengthListBase extends dart.mixin(FixedLengthListMixin$(E)) {}
+    class FixedLengthListBase extends dart.mixin(collection.ListBase$(E), FixedLengthListMixin$(E)) {}
     return FixedLengthListBase;
   });
   let FixedLengthListBase = FixedLengthListBase$();
   let UnmodifiableListBase$ = dart.generic(function(E) {
-    class UnmodifiableListBase extends dart.mixin(UnmodifiableListMixin$(E)) {}
+    class UnmodifiableListBase extends dart.mixin(collection.ListBase$(E), UnmodifiableListMixin$(E)) {}
     return UnmodifiableListBase;
   });
   let UnmodifiableListBase = UnmodifiableListBase$();
   let _backedList = dart.JsSymbol('_backedList');
   class _ListIndicesIterable extends ListIterable$(core.int) {
     _ListIndicesIterable(backedList) {
       this[_backedList] = backedList;
       super.ListIterable();
     }
     get [core.$length]() {
@@ skipping 565 matching lines @@
   exports.ReversedListIterable = ReversedListIterable;
   exports.UnmodifiableListError = UnmodifiableListError;
   exports.NonGrowableListError = NonGrowableListError;
   exports.makeListFixedLength = makeListFixedLength;
   exports.Lists = Lists;
   exports.printToConsole = printToConsole;
   exports.Sort = Sort;
   exports.Symbol = Symbol;
   exports.POWERS_OF_TEN = POWERS_OF_TEN;
 })(_internal || (_internal = {}));