Remove dart:codec and move classes into dart:convert.

sdk/lib/codec/encoding.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.codec;
-
-/**
- * Open-ended Encoding enum.
- */
-// TODO(floitsch): dart:io already has an Encoding class. If we can't
-// consolitate them, we need to remove `Encoding` here.
-abstract class Encoding extends Codec<String, List<int>> {
-  const Encoding();
-}
-
-// TODO(floitsch): add other encodings, like ASCII and ISO_8859_1.
-const UTF8 = const Utf8Codec();
-
-/**
- * A [Utf8Codec] encodes strings to utf-8 code units (bytes) and decodes
- * UTF-8 code units to strings.
- */
-class Utf8Codec extends Encoding {
-  final bool _allowMalformed;
-
-  /**
-   * Instantiates a new [Utf8Codec].
-   *
-   * The optional [allowMalformed] argument defines how [decoder] (and [decode])
-   * deal with invalid or unterminated character sequences.
-   *
-   * If it is `true` (and not overriden at the method invocation) [decode] and
-   * the [decoder] replace invalid (or unterminated) octet
-   * sequences with the Unicode Replacement character `U+FFFD` (�). Otherwise
-   * they throw a [FormatException].
-   */
-  const Utf8Codec({ bool allowMalformed: false })
-      : _allowMalformed = allowMalformed;
-
-  /**
-   * Decodes the UTF-8 [codeUnits] (a list of unsigned 8-bit integers) to the
-   * corresponding string.
-   *
-   * If [allowMalformed] is `true` the decoder replaces invalid (or
-   * unterminated) character sequences with the Unicode Replacement character
-   * `U+FFFD` (�). Otherwise it throws a [FormatException].
-   *
-   * If [allowMalformed] is not given, it defaults to the `allowMalformed` that
-   * was used to instantiate `this`.
-   */
-  String decode(List<int> codeUnits, { bool allowMalformed }) {
-    if (allowMalformed == null) allowMalformed = _allowMalformed;
-    return new Utf8Decoder(allowMalformed: allowMalformed).convert(codeUnits);
-  }
-
-  Converter<String, List<int>> get encoder => new Utf8Encoder();
-  Converter<List<int>, String> get decoder {
-    return new Utf8Decoder(allowMalformed: _allowMalformed);
-  }
-}