merge class extensions from patch files

test/generated_sdk/lib/collection/linked_hash_map.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.
 
 part of dart.collection;
 
 /**
  * A hash-table based implementation of [Map].
  *
  * The insertion order of keys is remembered,
@@ skipping 118 matching lines @@
    * If [keys] contains the same object multiple times, the last occurrence
    * overwrites the previous value.
    *
    * It is an error if the two [Iterable]s don't have the same length.
    */
   factory LinkedHashMap.fromIterables(Iterable<K> keys, Iterable<V> values) {
     LinkedHashMap<K, V> map = new LinkedHashMap<K, V>();
     Maps._fillMapWithIterables(map, keys, values);
     return map;
   }
+
+  @NoInline()
+  factory LinkedHashMap._literal(List keyValuePairs) {
+    return fillLiteralMap(keyValuePairs, new _LinkedHashMap<K, V>());
+  }
+
+  @NoThrows() @NoInline()
+  factory LinkedHashMap._empty() {
+    return new _LinkedHashMap<K, V>();
+  }
 }