dart:io | Split raw_server_socket_cancel test off from raw_socket_test.

tests/standalone/io/raw_server_socket_cancel_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
+
+import "dart:async";
+import "dart:io";
+import "dart:isolate";
+
+void testCancelResubscribeServerSocket() {
+  const int socketCount = 10;
+  var acceptCount = 0;
+  var doneCount = 0;
+  var closeCount = 0;
+  var errorCount = 0;
+
+  ReceivePort port = new ReceivePort();
+
+  RawServerSocket.bind().then((server) {
+    Expect.isTrue(server.port > 0);
+
+    void checkDone() {
+      if (doneCount == socketCount &&
+          closeCount + errorCount == socketCount) {
+        port.close();
+      }
+    }
+
+    // Subscribe the server socket. Then cancel subscription and
+    // subscribe again.
+    var subscription;
+    subscription = server.listen((client) {
+      if (++acceptCount == socketCount / 2) {
+        subscription.cancel();
+        Timer.run(() {
+          subscription = server.listen((_) {
+            // Close on cancel, so no more events.
+            Expect.fail("Event after closed through cancel");
+          });
+        });
+      }
+      // Close the client socket.
+      client.close();
+    });
+
+    // Connect a number of sockets.
+    for (int i = 0; i < socketCount; i++) {
+      RawSocket.connect("127.0.0.1", server.port).then((socket) {
+        socket.writeEventsEnabled = false;
+        var subscription;
+        subscription = socket.listen((event) {
+          Expect.equals(RawSocketEvent.READ_CLOSED, event);
+          socket.close();
+          closeCount++;
+          checkDone();
+        },
+        onDone: () { doneCount++; checkDone(); },
+        onError: (e) { errorCount++; checkDone(); });
+      }).catchError((e) {
+        errorCount++; checkDone();
+      });
+    }
+  });
+}
+
+void main() {
+  testCancelResubscribeServerSocket();
+}