Revert "Use relative URIs for core library part-of statements."

tests/standalone/io/web_socket_error_test.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.
 //
 // VMOptions=
 // VMOptions=--short_socket_read
 // VMOptions=--short_socket_write
 // VMOptions=--short_socket_read --short_socket_write
 // OtherResources=certificates/server_chain.pem
 // OtherResources=certificates/server_key.pem
 
 library dart.io;
 
 import "dart:async";
-import "dart:convert" show BASE64;
 import "dart:io";
 import "dart:math";
 import "dart:typed_data";
 
 import "package:async_helper/async_helper.dart";
 import "package:expect/expect.dart";
 import "package:path/path.dart";
 
-import "hash_utils.dart";
+part "../../../sdk/lib/io/crypto.dart";
 
 const String webSocketGUID = "258EAFA5-E914-47DA-95CA-C5AB0DC85B11";
 const String CERT_NAME = 'localhost_cert';
 const String HOST_NAME = 'localhost';
 
 String localFile(path) => Platform.script.resolve(path).toFilePath();
 
 SecurityContext serverContext = new SecurityContext()
   ..useCertificateChain(localFile('certificates/server_chain.pem'))
   ..usePrivateKey(localFile('certificates/server_key.pem'),
@@ skipping 19 matching lines @@
       WebSocket.connect('${secure ? "wss" : "ws"}://$HOST_NAME:$port/');
 
   void testForceCloseServerEnd(int totalConnections) {
     createServer().then((server) {
       server.listen((request) {
         var response = request.response;
         response.statusCode = HttpStatus.SWITCHING_PROTOCOLS;
         response.headers.set(HttpHeaders.CONNECTION, "upgrade");
         response.headers.set(HttpHeaders.UPGRADE, "websocket");
         String key = request.headers.value("Sec-WebSocket-Key");
-        var sha1 = new SHA1();
+        _SHA1 sha1 = new _SHA1();
         sha1.add("$key$webSocketGUID".codeUnits);
-        String accept = BASE64.encode(sha1.close());
+        String accept = _CryptoUtils.bytesToBase64(sha1.close());
         response.headers.add("Sec-WebSocket-Accept", accept);
         response.headers.contentLength = 0;
         response.detachSocket().then((socket) {
           socket.destroy();
         });
       });
 
       int closeCount = 0;
       for (int i = 0; i < totalConnections; i++) {
         createClient(server.port).then((webSocket) {
@@ skipping 16 matching lines @@
   }
 }
 
 main() {
   asyncStart();
   new SecurityConfiguration(secure: false).runTests();
   // TODO(whesse): WebSocket.connect needs an optional context: parameter
   // new SecurityConfiguration(secure: true).runTests();
   asyncEnd();
 }