Ensure raw_io creates all parent directories of the backing_dir.

recipe_modules/raw_io/api.py

 # -*- encoding: utf-8 -*-
 # Copyright 2014 The LUCI Authors. All rights reserved.
 # Use of this source code is governed under the Apache License, Version 2.0
 # that can be found in the LICENSE file.
 
 from recipe_engine import recipe_api
 from recipe_engine import util as recipe_util
 
 import os
 import shutil
@@ skipping 120 matching lines @@
   def backing_file(self):  # pragma: no cover
     raise ValueError('Output dir placeholders can not be used for stdin, '
                      'stdout or stderr')
 
   def render(self, test):
     assert not self._backing_dir, 'Placeholder can be used only once'
     if self.leak_to:
       self._backing_dir = str(self.leak_to)
       if not test.enabled: # pragma: no cover
         if not os.path.exists(self._backing_dir):
-          os.mkdir(self._backing_dir)
+          os.makedirs(self._backing_dir)
     else:
       if not test.enabled: # pragma: no cover
         self._backing_dir = tempfile.mkdtemp(suffix=self.suffix)
       else:
         self._backing_dir = '/path/to/tmp/' + self.suffix
 
     return [self._backing_dir]
 
   def result(self, presentation, test):
     assert self._backing_dir
@@ skipping 80 matching lines @@
     """Returns a directory Placeholder for use as a step argument.
 
     If 'leak_to' is None, the placeholder is backed by a temporary dir with
     a suffix 'suffix'. The dir is deleted when the step finishes.
 
     If 'leak_to' is not None, then it should be a Path and placeholder
     redirects IO to a dir at that path. Once step finishes, the dir is
     NOT deleted (i.e. it's 'leaking'). 'suffix' is ignored in that case.
     """
     return OutputDataDirPlaceholder(suffix, leak_to, name=name)