cleanup patch generation to preseve comments and remove @patch

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,
  * and keys are iterated in the order they were inserted into the map.
  * Values are iterated in their corresponding key's order.
  * Changing a key's value, when the key is already in the map,
  * does not change the iteration order,
  * but removing the key and adding it again
  * will make it be last in the iteration order.
  *
  * The keys of a `LinkedHashMap` must have consistent [Object.operator==]
  * and [Object.hashCode] implementations. This means that the `==` operator
  * must define a stable equivalence relation on the keys (reflexive,
  * symmetric, transitive, and consistent over time), and that `hashCode`
  * must be the same for objects that are considered equal by `==`.
  *
  * The map allows `null` as a key.
  */
 abstract class LinkedHashMap<K, V> implements HashMap<K, V> {
-  @patch
+  /**
+   * Creates an insertion-ordered hash-table based [Map].
+   *
+   * If [equals] is provided, it is used to compare the keys in the table with
+   * new keys. If [equals] is omitted, the key's own [Object.operator==] is used
+   * instead.
+   *
+   * Similar, if [hashCode] is provided, it is used to produce a hash value
+   * for keys in order to place them in the hash table. If it is omitted, the
+   * key's own [Object.hashCode] is used.
+   *
+   * If using methods like [operator[]], [remove] and [containsKey] together
+   * with a custom equality and hashcode, an extra `isValidKey` function
+   * can be supplied. This function is called before calling [equals] or
+   * [hashCode] with an argument that may not be a [K] instance, and if the
+   * call returns false, the key is assumed to not be in the set.
+   * The [isValidKey] function defaults to just testing if the object is a
+   * [K] instance.
+   *
+   * The used `equals` and `hashCode` method should always be consistent,
+   * so that if `equals(a, b)` then `hashCode(a) == hashCode(b)`. The hash
+   * of an object, or what it compares equal to, should not change while the
+   * object is in the table. If it does change, the result is unpredictable.
+   *
+   * If you supply one of [equals] and [hashCode],
+   * you should generally also to supply the other.
+   * An example would be using [identical] and [identityHashCode],
+   * which is equivalent to using the shorthand [LinkedHashMap.identity]).
+   */
   factory LinkedHashMap({ bool equals(K key1, K key2),
                           int hashCode(K key),
                           bool isValidKey(potentialKey) }) {
     if (isValidKey == null) {
       if (hashCode == null) {
         if (equals == null) {
           return new _LinkedHashMap<K, V>();
         }
         hashCode = _defaultHashCode;
       } else {
         if (identical(identityHashCode, hashCode) &&
             identical(identical, equals)) {
           return new _LinkedIdentityHashMap<K, V>();
         }
         if (equals == null) {
           equals = _defaultEquals;
         }
       }
     } else {
       if (hashCode == null) {
         hashCode = _defaultHashCode;
       }
       if (equals == null) {
         equals = _defaultEquals;
       }
     }
     return new _LinkedCustomHashMap<K, V>(equals, hashCode, isValidKey);
   }
 
-  @patch
+  /**
+   * Creates an insertion-ordered identity-based map.
+   *
+   * Effectively a shorthand for:
+   *
+   *     new LinkedHashMap(equals: identical, hashCode: identityHashCodeOf)
+   */
   factory LinkedHashMap.identity() = _LinkedIdentityHashMap<K, V>;
 
   /**
    * Creates a [LinkedHashMap] that contains all key value pairs of [other].
    */
   factory LinkedHashMap.from(Map other) {
     LinkedHashMap<K, V> result = new LinkedHashMap<K, V>();
     other.forEach((k, v) { result[k] = v; });
     return result;
   }
@@ skipping 28 matching lines @@
    * 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;
   }
 }