Some more removals of dart:utf.

tests/corelib/uri_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.
 
 library uriTest;
 
 import "package:expect/expect.dart";
-import 'dart:utf';
+import 'dart:convert';
 
 testUri(String uri, bool isAbsolute) {
   Expect.equals(isAbsolute, Uri.parse(uri).isAbsolute);
   Expect.stringEquals(uri, Uri.parse(uri).toString());
 
   // Test equals and hashCode members.
   Expect.equals(Uri.parse(uri), Uri.parse(uri));
   Expect.equals(Uri.parse(uri).hashCode, Uri.parse(uri).hashCode);
 }
 
@@ skipping 179 matching lines @@
       () => Uri.parse("http://:80").origin,
       (e) { return e is StateError; },
       "origin for uri with empty host should fail");
   Expect.throws(
       () => Uri.parse("file://localhost/test.txt").origin,
       (e) { return e is StateError; },
       "origin for non-http/https uri should fail");
 
   // URI encode tests
   // Create a string with code point 0x10000 encoded as a surrogate pair.
-  var s = decodeUtf8([0xf0, 0x90, 0x80, 0x80]);
+  var s = UTF8.decode([0xf0, 0x90, 0x80, 0x80]);
 
   Expect.stringEquals("\u{10000}", s);
 
   testEncodeDecode("A + B", "A%20%2B%20B");
   testEncodeDecode("\uFFFE", "%EF%BF%BE");
   testEncodeDecode("\uFFFF", "%EF%BF%BF");
   testEncodeDecode("\uFFFE", "%EF%BF%BE");
   testEncodeDecode("\uFFFF", "%EF%BF%BF");
   testEncodeDecode("\x7f", "%7F");
   testEncodeDecode("\x80", "%C2%80");
   testEncodeDecode("\u0800", "%E0%A0%80");
   testEncodeDecode(":/@',;?&=+\$", ":/@',;?&=%2B\$");
   testEncodeDecode(s, "%F0%90%80%80");
   testEncodeDecodeComponent("A + B", "A%20%2B%20B");
   testEncodeDecodeComponent("\uFFFE", "%EF%BF%BE");
   testEncodeDecodeComponent("\uFFFF", "%EF%BF%BF");
   testEncodeDecodeComponent("\uFFFE", "%EF%BF%BE");
   testEncodeDecodeComponent("\uFFFF", "%EF%BF%BF");
   testEncodeDecodeComponent("\x7f", "%7F");
   testEncodeDecodeComponent("\x80", "%C2%80");
   testEncodeDecodeComponent("\u0800", "%E0%A0%80");
   testEncodeDecodeComponent(":/@',;?&=+\$", "%3A%2F%40'%2C%3B%3F%26%3D%2B%24");
   testEncodeDecodeComponent(s, "%F0%90%80%80");
   testEncodeDecodeQueryComponent("A + B", "A+%2B+B");
 }