Signal handling, take 2.

sdk/lib/_internal/lib/io_patch.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.
 
 patch class _Directory {
   patch static _current() {
     throw new UnsupportedError("Directory._current");
   }
   patch static _setCurrent(path) {
     throw new UnsupportedError("Directory_SetCurrent");
@@ skipping 167 matching lines @@
   }
   patch static void _setExitCode(int status) {
     throw new UnsupportedError("ProcessUtils._setExitCode");
   }
   patch static void _sleep(int millis) {
     throw new UnsupportedError("ProcessUtils._sleep");
   }
   patch static int _pid(Process process) {
     throw new UnsupportedError("ProcessUtils._pid");
   }
+  patch static Stream<ProcessSignal> _watchSignal(ProcessSignal signal) {
+    throw new UnsupportedError("ProcessUtils._watchSignal");
+  }
 }
 
 patch class Process {
   patch static Future<Process> start(
       String executable,
       List<String> arguments,
       {String workingDirectory,
        Map<String, String> environment,
        bool includeParentEnvironment: true,
        bool runInShell: false}) {
@@ skipping 182 matching lines @@
   patch static bool get isSupported {
     throw new UnsupportedError("_FileSystemWatcher.isSupported");
   }
 }
 
 patch class _IOService {
   patch static Future dispatch(int request, List data) {
     throw new UnsupportedError("_IOService.dispatch");
   }
 }