Roll recipe dependencies (trivial).

This is an automated CL created by the recipe roller. This CL rolls recipe
changes from upstream projects (e.g. depot_tools) into downstream projects
(e.g. tools/build).


More info is at https://goo.gl/zkKdpD. Use https://goo.gl/noib3a to file a bug
(or complain)

recipe_engine:
  https://crrev.com/4439877a3ea1acd4c3f4cf805fba138aeb5b16a5 [test_test.py] make root_dir realpath. (iannucci@chromium.org)

TBR=iannucci@chromium.org

Change-Id: I1193412f8908a0dfedfbde6ac5a0abe362b564d5
Recipe-Tryjob-Bypass-Reason: Autoroller
Bugdroid-Send-Email: False
Reviewed-on: https://chromium-review.googlesource.com/459022
Reviewed-by: <recipe-roller@chromium.org>
Commit-Queue: <recipe-roller@chromium.org>

infra/config/recipes.cfg

@@ -4,7 +4,7 @@
     {
       "branch": "master", 
       "project_id": "recipe_engine", 
-      "revision": "e3bd68e54e94d7ec339fd7c8d90544975386f4fe", 
+      "revision": "4439877a3ea1acd4c3f4cf805fba138aeb5b16a5", 
       "url": "https://chromium.googlesource.com/external/github.com/luci/recipes-py.git"
     }
   ],