fuse List and js Array together and a few other misc fixes.

tool/input_sdk/patch/core_patch.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.
 
 // Patch file for dart:core classes.
 import "dart:_internal" as _symbol_dev;
 import 'dart:_interceptors';
 import 'dart:_js_helper' show patch,
                               checkInt,
                               getRuntimeType,
@@ skipping 224 matching lines @@
 }
 
 class _ListConstructorSentinel {
   const _ListConstructorSentinel();
 }
 
 // Patch for List implementation.
 @patch
 class List<E> {
   @patch
-  factory List([int length = const _ListConstructorSentinel()]) {

[Jennifer Messerly, 2015/04/22 21:14:19]

wow, craziness

[Jacob, 2015/04/22 22:58:32]

yep. this just in... 
new List() should fail checked mode on dart2js. :)

-    if (length == const _ListConstructorSentinel()) {
-      return new JSArray<E>.emptyGrowable();
+  factory List([int length]) {
+    if (length == null) {
+      return JS('', '[]');
     }
-    return new JSArray<E>.fixed(length);
+    // Explicit type test is necessary to guard against JavaScript conversions
+    // in unchecked mode.
+    if ((length is !int) || (length < 0)) {
+      throw new ArgumentError("Length must be a non-negative integer: $length");
+    }
+    var list = JS('', 'new Array(#)', length);
+    JS('void', r'#.fixed$length = Array', list);

[Jennifer Messerly, 2015/04/22 21:14:19]

maybe TODO to revisit this? e.g. TODO(jmesserly): consider a fixed array
subclass instead

[Jacob, 2015/04/22 22:58:32]

Done. I like adding TODO(jmesserly) better than TODO(jacobr)

+    return list;
   }
 
   @patch
   factory List.filled(int length, E fill) {
     List result = new JSArray<E>.fixed(length);
     if (length != 0 && fill != null) {
       for (int i = 0; i < result.length; i++) {
         result[i] = fill;
       }
     }
@@ skipping 189 matching lines @@
   @patch
   static bool get _isWindows => false;
 
   @patch
   static Uri get base {
     String uri = Primitives.currentUri();
     if (uri != null) return Uri.parse(uri);
     throw new UnsupportedError("'Uri.base' is not supported");
   }
 }