Revert "Move dart2js from sdk/lib/_internal/compiler to pkg/compiler"

pkg/compiler/lib/src/colors.dart

-// 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.
-
-library colors;
-
-// See http://en.wikipedia.org/wiki/ANSI_escape_code#CSI_codes
-const String RESET = '\u001b[0m';
-
-// See http://en.wikipedia.org/wiki/ANSI_escape_code#Colors
-const String BLACK_COLOR = '\u001b[30m';
-const String RED_COLOR = '\u001b[31m';
-const String GREEN_COLOR = '\u001b[32m';
-const String YELLOW_COLOR = '\u001b[33m';
-const String BLUE_COLOR = '\u001b[34m';
-const String MAGENTA_COLOR = '\u001b[35m';
-const String CYAN_COLOR = '\u001b[36m';
-const String WHITE_COLOR = '\u001b[37m';
-
-String wrap(String string, String color) => "${color}$string${RESET}";
-
-String black(String string) => wrap(string, BLACK_COLOR);
-String red(String string) => wrap(string, RED_COLOR);
-String green(String string) => wrap(string, GREEN_COLOR);
-String yellow(String string) => wrap(string, YELLOW_COLOR);
-String blue(String string) => wrap(string, BLUE_COLOR);
-String magenta(String string) => wrap(string, MAGENTA_COLOR);
-String cyan(String string) => wrap(string, CYAN_COLOR);
-String white(String string) => wrap(string, WHITE_COLOR);