cleanup patch generation to preseve comments and remove @patch

test/generated_sdk/lib/collection/hash_set.dart

Index: test/generated_sdk/lib/collection/hash_set.dart
diff --git a/test/generated_sdk/lib/collection/hash_set.dart b/test/generated_sdk/lib/collection/hash_set.dart
index ed645e6058dcd64949abe6b02c0fe94585248971..2a84cad4975b00a69a7892c6eb4883edba3a4033 100644
--- a/test/generated_sdk/lib/collection/hash_set.dart
+++ b/test/generated_sdk/lib/collection/hash_set.dart
@@ -50,7 +50,27 @@ abstract class _HashSetBase<E> extends SetBase<E> {
  * codes of objects are well distributed.
  */
 abstract class HashSet<E> implements Set<E> {
-  @patch
+  /**
+   * Create a hash set using the provided [equals] as equality.
+   *
+   * The provided [equals] must define a stable equivalence relation, and
+   * [hashCode] must be consistent with [equals]. If the [equals] or [hashCode]
+   * methods won't work on all objects, but only to instances of E, the
+   * [isValidKey] predicate can be used to restrict the keys that they are
+   * applied to. Any key for which [isValidKey] returns false is automatically
+   * assumed to not be in the set.
+   *
+   * If [equals] or [hashCode] are omitted, the set uses
+   * the objects' intrinsic [Object.operator==] and [Object.hashCode].
+   *
+   * If [isValidKey] is omitted, it defaults to testing if the object is an
+   * [E] instance.
+   *
+   * 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 [LinkedSet.identity]).
+   */
   factory HashSet({ bool equals(E e1, E e2),
                     int hashCode(E e),
                     bool isValidKey(potentialKey) }) {
@@ -80,7 +100,13 @@ abstract class HashSet<E> implements Set<E> {
     return new _CustomHashSet<E>(equals, hashCode, isValidKey);
   }
 
-  @patch
+  /**
+   * Creates an unordered identity-based set.
+   *
+   * Effectively a shorthand for:
+   *
+   *     new HashSet(equals: identical, hashCode: identityHashCodeOf)
+   */
   factory HashSet.identity() = _IdentityHashSet<E>;
 
   /**