Start accepting incoming sockets earlier on Windows, to associate a at AcceptEx error to 'ServerSoc…

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 395 matching lines @@
   if (NO_RETRY_EXPECTED(listen(fd, backlog > 0 ? backlog : SOMAXCONN)) != 0) {
     VOID_TEMP_FAILURE_RETRY(close(fd));
     return -1;
   }
 
   Socket::SetNonBlocking(fd);
   return fd;
 }
 
 
+bool ServerSocket::StartAccept(intptr_t fd) {
+  USE(fd);
+  return true;
+}
+
+
 intptr_t ServerSocket::Accept(intptr_t fd) {
   intptr_t socket;
   struct sockaddr clientaddr;
   socklen_t addrlen = sizeof(clientaddr);
   socket = TEMP_FAILURE_RETRY(accept(fd, &clientaddr, &addrlen));
   if (socket == -1) {
     if (errno == EAGAIN) {
       // We need to signal to the caller that this is actually not an
       // error. We got woken up from the poll on the listening socket,
       // but there is no connection ready to be accepted.
@@ skipping 187 matching lines @@
 
 bool Socket::LeaveMulticast(
     intptr_t fd, RawAddr* addr, RawAddr* interface, int interfaceIndex) {
   return JoinOrLeaveMulticast(fd, addr, interface, interfaceIndex, false);
 }
 
 }  // namespace bin
 }  // namespace dart
 
 #endif  // defined(TARGET_OS_MACOS)