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

pkg/serialization/lib/src/serialization_rule.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.
 
 part of serialization;
 
 // TODO(alanknight): We should have an example and tests for subclassing
 // serialization rule rather than using the hard-coded ClosureToMap rule. And
 // possibly an abstract superclass that's designed to be subclassed that way.
 /**
@@ skipping 390 matching lines @@
     var separatorIndex = qualifiedName.lastIndexOf(".");
     var type = qualifiedName.substring(separatorIndex + 1);
     var lookup = r.objectNamed(type, (x) => null);
     if (lookup != null) return lookup;
     var name = qualifiedName.substring(0, separatorIndex);
     // This is very ugly. The library name for an unnamed library is its URI.
     // That can't be constructed as a Symbol, so we can't use findLibrary.
     // So follow one or the other path depending if it has a colon, which we
     // assume is in any URI and can't be in a Symbol.
     if (name.contains(":")) {
-      var uri = new Uri(name);
+      var uri = Uri.parse(name);
       var libMirror = currentMirrorSystem().libraries[uri];
       return libMirror.classes[new Symbol(type)];
     } else {
       var symbol = new Symbol(name);
       var typeSymbol = new Symbol(type);
       var libMirror = currentMirrorSystem().findLibrary(symbol).firstWhere(
         (lib) => lib.classes[typeSymbol] != null);
       return libMirror.classes[typeSymbol];
     }
   }
@@ skipping 179 matching lines @@
   removeWhere(x) => _throw();
   retainWhere(x) => _throw();
   replaceRange(x, y, z) => _throw();
   getRange(x, y) => _throw();
   setRange(x, y, z, [a = 0]) => _throw();
   setAll(x, y) => _throw();
   removeRange(x, y) => _throw();
   get reversed => _throw();
   void set length(x) => _throw();
 }