Bug 1399100 - fix client.py follow-up, r=kaie

MozReview-Commit-ID: V8nVlkRenv

--HG--
extra : rebase_source : 206d04cca2c635d0879880c72287231b433c7368

client.py

@@ -112,6 +112,7 @@ def update_nspr_or_nss(tag, depfile, destination, hgpath):
     sys.exit(2)
   warn_if_patch_exists(permanent_patch_dir)
   # protect patch directory from being removed by do_hg_replace
+  if os.path.exists(permanent_patch_dir):
     shutil.move(permanent_patch_dir, temporary_patch_dir)
   # now update the destination
   print "reverting to HG version of %s to get its blank line state" % depfile
@@ -127,6 +128,7 @@ def update_nspr_or_nss(tag, depfile, destination, hgpath):
   tag_file = destination + "/TAG-INFO"
   print >>file(tag_file, "w"), tag
   # move patch directory back to a subdirectory
+  if os.path.exists(temporary_patch_dir):
     shutil.move(temporary_patch_dir, permanent_patch_dir)
 
 def warn_if_patch_exists(path):