Fix comment from earlier commit.

runtime/bin/socket_macos.cc

 // 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.
 
 #include "platform/globals.h"
 #if defined(TARGET_OS_MACOS)
 
 #include <errno.h>  // NOLINT
 #include <stdio.h>  // NOLINT
 #include <stdlib.h>  // NOLINT
@@ skipping 306 matching lines @@
   if (TEMP_FAILURE_RETRY(
           bind(fd,
                &addr.addr,
                SocketAddress::GetAddrLength(&addr))) < 0) {
     VOID_TEMP_FAILURE_RETRY(close(fd));
     return -1;
   }
 
   // Test for invalid socket port 65535 (some browsers disallow it).
   if (port == 0 && Socket::GetPort(fd) == 65535) {
-    // Don't close fd until we have created new. By doing that we ensure another
-    // port.
+    // Don't close the socket until we have created a new socket, ensuring
+    // that we do not get the bad port number again.
     intptr_t new_fd = CreateBindListen(addr, 0, backlog, v6_only);
     int err = errno;
     VOID_TEMP_FAILURE_RETRY(close(fd));
     errno = err;
     return new_fd;
   }
 
   if (TEMP_FAILURE_RETRY(listen(fd, backlog > 0 ? backlog : SOMAXCONN)) != 0) {
     VOID_TEMP_FAILURE_RETRY(close(fd));
     return -1;
@@ skipping 52 matching lines @@
                                        IPPROTO_TCP,
                                        TCP_NODELAY,
                                        reinterpret_cast<char *>(&on),
                                        sizeof(on))) == 0;
 }
 
 }  // namespace bin
 }  // namespace dart
 
 #endif  // defined(TARGET_OS_MACOS)