ninja/mac: Try to fix 'IOError: [Errno 2] No such file or directory' error.

pylib/gyp/generator/ninja.py

 # Copyright (c) 2013 Google Inc. All rights reserved.
 # Use of this source code is governed by a BSD-style license that can be
 # found in the LICENSE file.
 
 import copy
 import hashlib
 import multiprocessing
 import os.path
 import re
 import signal
@@ skipping 378 matching lines @@
       arch = self.msvs_settings.GetArch(config_name)
       self.ninja.variable('arch', self.win_env[arch])
       self.ninja.variable('cc', '$cl_' + arch)
       self.ninja.variable('cxx', '$cl_' + arch)
 
     if self.flavor == 'mac':
       self.archs = self.xcode_settings.GetActiveArchs(config_name)
       if len(self.archs) > 1:
         self.arch_subninjas = dict(
             (arch, ninja_syntax.Writer(
-                open(os.path.join(self.toplevel_build,
-                                  self._SubninjaNameForArch(arch)),
-                     'w')))
+                OpenOutput(os.path.join(self.toplevel_build,
+                                        self._SubninjaNameForArch(arch)),
+                           'w')))
             for arch in self.archs)
 
     # Compute predepends for all rules.
     # actions_depends is the dependencies this target depends on before running
     # any of its action/rule/copy steps.
     # compile_depends is the dependencies this target depends on before running
     # any of its compile steps.
     actions_depends = []
     compile_depends = []
     # TODO(evan): it is rather confusing which things are lists and which
@@ skipping 1714 matching lines @@
           arglists.append(
               (target_list, target_dicts, data, params, config_name))
         pool.map(CallGenerateOutputForConfig, arglists)
       except KeyboardInterrupt, e:
         pool.terminate()
         raise e
     else:
       for config_name in config_names:
         GenerateOutputForConfig(target_list, target_dicts, data, params,
                                 config_name)