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

tests/compiler/dart2js/backend_htype_list_test.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.
 
 import "package:expect/expect.dart";
 import '../../../sdk/lib/_internal/compiler/implementation/js_backend/js_backend.dart';
 import '../../../sdk/lib/_internal/compiler/implementation/ssa/ssa.dart';
 
 import 'compiler_helper.dart';
 import 'parser_helper.dart';
@@ skipping 11 matching lines @@
 List<HType> IBS;
 List<HType> IIS;
 List<HType> BII;
 List<HType> IBI;
 List<HType> IIB;
 List<HType> III;
 
 FunctionSignature compileAndFindSignature(String code,
                                           String className,
                                           String memberName) {
-  Uri uri = new Uri.fromComponents(scheme: 'source');
+  Uri uri = new Uri(scheme: 'source');
   var compiler = compilerFor(code, uri);
   compiler.runCompiler(uri);
   var cls = findElement(compiler, className);
   var member = cls.lookupLocalMember(buildSourceString(memberName));
   var signature = member.computeSignature(compiler);
   return signature;
 }
 
 HTypeList createHTypeList(List<HType> types) {
   HTypeList result = new HTypeList(types.length);
@@ skipping 191 matching lines @@
   IIB = <HType>[HType.INTEGER, HType.INTEGER, HType.BOOLEAN];
   III = <HType>[HType.INTEGER, HType.INTEGER, HType.INTEGER];
 
   test1();
   test2_1();
   test2_2();
   test2_3();
   test3_1();
   test4();
 }