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

tests/compiler/dart2js/compiler_helper.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.
 // Test constant folding.
 
 library compiler_helper;
 
 import "package:expect/expect.dart";
-import 'dart:uri';
-export 'dart:uri' show Uri;
 
 import '../../../sdk/lib/_internal/compiler/implementation/elements/elements.dart'
        as lego;
 export '../../../sdk/lib/_internal/compiler/implementation/elements/elements.dart';
 
 import '../../../sdk/lib/_internal/compiler/implementation/js_backend/js_backend.dart'
        as js;
 
 import '../../../sdk/lib/_internal/compiler/implementation/dart2jslib.dart'
        as leg;
@@ skipping 62 matching lines @@
                           String coreSource: DEFAULT_CORELIB}) {
   MockCompiler compiler = new MockCompiler(
       analyzeAll: analyzeAll,
       analyzeOnly: analyzeOnly,
       coreSource: coreSource);
   compiler.sourceFiles[uri.toString()] = new SourceFile(uri.toString(), code);
   return compiler;
 }
 
 String compileAll(String code, {String coreSource: DEFAULT_CORELIB}) {
-  Uri uri = new Uri.fromComponents(scheme: 'source');
+  Uri uri = new Uri(scheme: 'source');
   MockCompiler compiler = compilerFor(code, uri, coreSource: coreSource);
   compiler.runCompiler(uri);
   Expect.isFalse(compiler.compilationFailed,
                  'Unexpected compilation error');
   return compiler.assembledCode;
 }
 
 dynamic compileAndCheck(String code,
                         String name,
                         check(MockCompiler compiler, lego.Element element)) {
-  Uri uri = new Uri.fromComponents(scheme: 'source');
+  Uri uri = new Uri(scheme: 'source');
   MockCompiler compiler = compilerFor(code, uri);
   compiler.runCompiler(uri);
   lego.Element element = findElement(compiler, name);
   return check(compiler, element);
 }
 
 compileSources(Map<String, String> sources,
                check(MockCompiler compiler)) {
-  Uri base = new Uri.fromComponents(scheme: 'source');
+  Uri base = new Uri(scheme: 'source');
   Uri mainUri = base.resolve('main.dart');
   String mainCode = sources['main.dart'];
   Expect.isNotNull(mainCode, 'No source code found for "main.dart"');
   MockCompiler compiler = compilerFor(mainCode, mainUri);
 
   sources.forEach((String path, String code) {
     if (path == 'main.dart') return;
     compiler.registerSource(base.resolve(path), code);
   });
 
@@ skipping 84 matching lines @@
   final xRe = new RegExp('\\bx\\b');
   regexp = regexp.replaceAll(xRe, '(?:$anyIdentifier)');
   final spaceRe = new RegExp('\\s+');
   regexp = regexp.replaceAll(spaceRe, '(?:\\s*)');
   if (shouldMatch) {
     Expect.isTrue(new RegExp(regexp).hasMatch(generated));
   } else {
     Expect.isFalse(new RegExp(regexp).hasMatch(generated));
   }
 }