infra_paths: enable persistent cache also on Mac

recipe_modules/infra_paths/path_config.py

 # Copyright 2016 The Chromium Authors. All rights reserved.
 # Use of this source code is governed by a BSD-style license that can be
 # found in the LICENSE file.
 
 import DEPS
 CONFIG_CTX = DEPS['path'].CONFIG_CTX
 
 
 @CONFIG_CTX()
 def infra_common(c):
@@ skipping 15 matching lines @@
 
 
 @CONFIG_CTX(includes=['infra_common'])
 def infra_kitchen(c):
   c.base_paths['root'] = c.CURRENT_WORKING_DIR
   c.base_paths['slave_build'] = c.CURRENT_WORKING_DIR
   # TODO(phajdan.jr): have one cache dir, let clients append suffixes.
   # TODO(phajdan.jr): set persistent cache path for remaining platforms.
   # NOTE: do not use /b/swarm_slave here - it gets deleted on bot redeploy,
   # and may happen even after a reboot.
-  if c.PLATFORM == 'linux':
+  if c.PLATFORM in ('linux', 'mac'):
     c.base_paths['cache'] = (
         '/', 'b', 'cache', 'chromium')
     for path in ('builder_cache', 'git_cache', 'goma_cache', 'goma_deps_cache'):
       c.base_paths[path] = c.base_paths['cache'] + (path,)
   else:
     c.base_paths['cache'] = c.base_paths['root'] + ('cache',)
     c.base_paths['git_cache'] = c.base_paths['root'] + ('cache_dir',)
     for path in ('builder_cache', 'goma_cache', 'goma_deps_cache'):
       c.base_paths[path] = c.base_paths['cache'] + (path,)