Merge the dart:uri library into dart:core and update the Uri class

sdk/lib/_internal/compiler/samples/darttags/darttags.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.
 
 // Usage: Add the following to your .gclient file (found in the parent
 // of the "dart" in a gclient checkout of the Dart repositor).
 //
 // hooks = [
 //   {
 //     "pattern": ".",
 //     "action": [
 //       "dart/sdk/bin/dart",
 //       "dart/sdk/lib/_internal/compiler/samples/darttags/darttags.dart",
 //       "dart/TAGS"
 //     ],
 //   },
 // ]
 //
 // Modify .emacs to contain:
 //
 //      (setq tags-table-list
 //           '("DART_LOCATION/dart"))
 //
 // Where DART_LOCATION is the gclient directory where you found .gclient.
 
 import 'dart:io';
-import 'dart:uri';
 
 // TODO(ahe): Should be dart:mirrors.
 import '../../implementation/mirrors/mirrors.dart';
 
 import '../../../libraries.dart'
     show LIBRARIES, LibraryInfo;
 
 import '../../implementation/mirrors/dart2js_mirror.dart'
     show analyze, BackDoor;
 
@@ skipping 90 matching lines @@
 
   var tag_definition_data = '$buffer';
   var src_file = relativize(outputUri, uri, false);
   var size_of_tag_definition_data_in_bytes = tag_definition_data.length;
 
   // The header.
   output.writeStringSync(
       '\x0c\n${src_file},${size_of_tag_definition_data_in_bytes}\n');
   output.writeStringSync(tag_definition_data);
 }