Work around dart-lang/sdk#25348.

lib/src/executable.dart

 // Copyright (c) 2014, 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.
 
 library pub.executable;
 
 import 'dart:async';
 import 'dart:io';
 
 import 'package:barback/barback.dart';
@@ skipping 123 matching lines @@
   var process = await Process.start(Platform.executable, vmArgs);
 
   _forwardSignals(process);
 
   // Note: we're not using process.std___.pipe(std___) here because
   // that prevents pub from also writing to the output streams.
   process.stderr.listen(stderr.add);
   process.stdout.listen(stdout.add);
   stdin.listen(process.stdin.add);
 
-  return process.exitCode;
+  // Work around dart-lang/sdk#25348.
+  process.stdin.done.catchError((_) {});
+
+  return await process.exitCode;
 }
 
 /// Returns the URL the VM should use to load the executable at [path].
 ///
 /// [path] must be relative to the root of [package]. If [path] doesn't exist,
 /// returns `null`.
 Future<Uri> _executableUrl(Entrypoint entrypoint, String package, String path,
     {bool isGlobal: false, BarbackMode mode}) async {
   assert(p.isRelative(path));
 
@@ skipping 129 matching lines @@
 Future<int> _runCachedExecutable(Entrypoint entrypoint, String snapshotPath,
     List<String> args, {bool checked: false}) {
   return runSnapshot(snapshotPath, args,
       packagesFile: entrypoint.packagesFile,
       checked: checked,
       recompile: () {
     log.fine("Precompiled executable is out of date.");
     return entrypoint.precompileExecutables();
   });
 }