Move _StreamSinkImpl from dart:io to dart:async as StreamSinkAdapter.

runtime/bin/process_linux.cc

 // 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.
 
 #include "platform/globals.h"
 #if defined(TARGET_OS_LINUX)
 
 #include "bin/process.h"
 
 #include <errno.h>  // NOLINT
@@ skipping 656 matching lines @@
     if (kSignals[i] == signal) {
       found = true;
       break;
     }
   }
   if (!found) return -1;
   int fds[2];
   if (pipe(fds) != 0) {
     return -1;
   }
-  if (!FDUtils::SetNonBlocking(fds[0])) {
-    VOID_TEMP_FAILURE_RETRY(close(fds[0]));
-    VOID_TEMP_FAILURE_RETRY(close(fds[1]));
-    return -1;
-  }
   ThreadSignalBlocker blocker(kSignalsCount, kSignals);
   MutexLocker lock(signal_mutex);
   SignalInfo* handler = signal_handlers;
   bool listen = true;
   while (handler != NULL) {
     if (handler->signal() == signal) {
       listen = false;
       break;
     }
     handler = handler->next();
   }
   if (listen) {
     struct sigaction act;
     bzero(&act, sizeof(act));
     act.sa_handler = SignalHandler;
     sigemptyset(&act.sa_mask);
     for (int i = 0; i < kSignalsCount; i++) {
       sigaddset(&act.sa_mask, kSignals[i]);
     }
     int status = sigaction(signal, &act, NULL);
     if (status < 0) {
+      int err = errno;
       VOID_TEMP_FAILURE_RETRY(close(fds[0]));
       VOID_TEMP_FAILURE_RETRY(close(fds[1]));
+      errno = err;
       return -1;
     }
   }
   if (signal_handlers == NULL) {
     signal_handlers = new SignalInfo(fds[1], signal);
   } else {
     new SignalInfo(fds[1], signal, signal_handlers);
   }
   return fds[0];
 }
@@ skipping 24 matching lines @@
     bzero(&act, sizeof(act));
     act.sa_handler = SIG_DFL;
     sigaction(signal, &act, NULL);
   }
 }
 
 }  // namespace bin
 }  // namespace dart
 
 #endif  // defined(TARGET_OS_LINUX)