remove serialization. it's moved to github

pkg/serialization/lib/src/serialization_helpers.dart

Index: pkg/serialization/lib/src/serialization_helpers.dart
diff --git a/pkg/serialization/lib/src/serialization_helpers.dart b/pkg/serialization/lib/src/serialization_helpers.dart
deleted file mode 100644
index 52072670726bb7e9d5bbea7dda8f36ba86d4aab1..0000000000000000000000000000000000000000
--- a/pkg/serialization/lib/src/serialization_helpers.dart
+++ /dev/null
@@ -1,92 +0,0 @@
-// 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.
-
-/**
- * This contains extra functions and classes useful for implementing
- * serialiation. Some or all of these will be removed once the functionality is
- * available in the core library.
- */
-library serialization_helpers;
-
-import 'dart:collection';
-
-/**
- * A named function of one argument that just returns it. Useful for using
- * as a default value for a function parameter or other places where you want
- * to concisely provide a function that just returns its argument.
- */
-doNothing(x) => x;
-
-/** Concatenate two lists. Handle the case where one or both might be null. */
-// TODO(alanknight): Remove once issue 5342 is resolved.
-Iterable append(Iterable a, Iterable b) {
-  if (a == null) {
-    return (b == null) ? [] : new List.from(b);
-  }
-  if (b == null) return new List.from(a);
-  var result = new List.from(a);
-  result.addAll(b);
-  return result;
-}
-
-/** Helper function for PrimitiveRule to tell which objects it applies to. */
-bool isPrimitive(object) {
-  return identical(object, null) || object is num || object is String ||
-      identical(object, true) || identical(object, false);
-}
-
-/**
- * Given either an Iterable or a Map, return a map. For a Map just return it.
- * For an iterable, return a Map from the index to the value at that index.
- *
- * Used to iterate polymorphically between List-like and Map-like things.
- * For example, keysAndValues(["a", "b", "c"]).forEach((key, value) => ...);
- * will loop over the key/value pairs 1/"a", 2/"b", 3/"c", as if the argument
- * was a Map from integer keys to string values.
- */
-Map keysAndValues(x) {
-  if (x is Map) return x;
-  if (x is List) return x.asMap();
-  if (x is Iterable) return x.toList().asMap();
-  throw new ArgumentError("Invalid argument, expected Map or Iterable, got $x");
-}
-
-/**
- * Lets you iterate polymorphically between
- * List-like and Map-like things, but making them behave like Lists, instead
- * of behaving like Maps.
- * So values(["a", "b", "c"]).forEach((value) => ...);
- * will loop over the values "a", "b", "c", as if it were a List of values.
- * Only supports forEach() and map() operations because that was all I needed
- * for the moment.
- */
-Iterable values(x) {
-  if (x is Iterable) return x;
-  if (x is Map) return x.values;
-  throw new ArgumentError("Invalid argument, expected Map or Iterable, got $x");
-}
-
-/**
- * Iterate over [collection] and return a new collection of the same type
- * where each value has been transformed by [f]. For iterables and sets, this
- * is equivalent to [map]. For a Map, it returns a new Map with the same keys
- * and the corresponding values transformed by [f].
- */
-mapValues(collection, Function f) {
-  if (collection is Set) return collection.map(f).toSet();
-  if (collection is Iterable) return collection.map(f).toList();
-  if (collection is Map) return new Map.fromIterables(collection.keys,
-      collection.values.map(f));
-  throw new ArgumentError("Invalid argument, expected Map or Iterable, "
-      "got $collection");
-}
-
-/**
- * This acts as a stand-in for some value that cannot be hashed. We can't
- * just use const Object() because the compiler will fold them together.
- */
-class _Sentinel {
-  final _wrappedObject;
-  const _Sentinel(this._wrappedObject);
-}