Remove manifest-versions from options.perserve_paths

Remove manifest-versions from perserve_paths, so that clobber operation can
clean the previous manifest-versions.

BUG=chromium:519017
TEST=run_tests

Change-Id: I9b050cd252b44ec59b23b8dc8329bbd15958802b
Reviewed-on: https://chromium-review.googlesource.com/336289
Commit-Ready: Ningning Xia <nxia@chromium.org>
Tested-by: Chris Sosa <sosa@chromium.org>
Tested-by: Ningning Xia <nxia@chromium.org>
Reviewed-by: Chris Sosa <sosa@chromium.org>
diff --git a/scripts/cbuildbot.py b/scripts/cbuildbot.py
index 7cd1331..dff0d8c 100644
--- a/scripts/cbuildbot.py
+++ b/scripts/cbuildbot.py
@@ -1193,11 +1193,7 @@
     _BackupPreviousLog(log_file)
 
   with cros_build_lib.ContextManagerStack() as stack:
-    # TODO(ferringb): update this once
-    # https://chromium-review.googlesource.com/25359
-    # is landed- it's sensitive to the manifest-versions cache path.
-    options.preserve_paths = set(['manifest-versions', '.cache',
-                                  'manifest-versions-internal'])
+    options.preserve_paths = set()
     if log_file is not None:
       # We don't want the critical section to try to clean up the tee process,
       # so we run Tee (forked off) outside of it. This prevents a deadlock