Improve List implementation.

dart/frog/tests/leg/src/mock_compiler.dart

 // Copyright (c) 2012, 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.
 
 #library('mock_compiler');
 
 #import("../../../../lib/uri/uri.dart");
 
 #import("../../../leg/leg.dart");
 #import("../../../leg/elements/elements.dart");
 #import("../../../leg/tree/tree.dart");
 #import("../../../leg/util/util.dart");
 #import("parser_helper.dart");
 
 class WarningMessage {
   Node node;
   Message message;
   WarningMessage(this.node, this.message);
 
   toString() => message.toString();
 }
 
 final String DEFAULT_HELPERLIB = @'''
   lt() {} add(var a, var b) {} sub() {} mul() {} div() {} tdiv() {} mod() {}
   neg() {} shl() {} shr() {} eq() {} le() {} gt() {} ge() {}
   or() {} and() {} not() {} eqNull(a) {} eqq() {}
+  iae(x) {throw x;} ioore(x) {throw x;}
   guard$array(x) { return x; }
   guard$num(x) { return x; }
   guard$string(x) { return x; }
   guard$stringOrArray(x) { return x; }
   builtin$add$1(receiver, value) {}
   builtin$get$length(var receiver) {}
   builtin$filter$1(receiver, predicate) {}
   builtin$removeLast$0(receiver) {}
   index(a, index) {}
   indexSet(a, index, value) {}''';
@@ skipping 117 matching lines @@
       });
   }
 }
 
 LibraryElement mockLibrary(Compiler compiler, String source) {
   Uri uri = new Uri(scheme: "source");
   var library = new LibraryElement(new Script(uri, new MockFile(source)));
   importLibrary(library, compiler.coreLibrary, compiler);
   return library;
 }