Revert "Fix cros flash version handling"

This reverts commit ff75f3a8906c3b460cb1d841b24938bb883b6873.

This CL broke "cros flash" when using one of the standard channel commands:

for example:
cros flash ${IP} xbuddy://remote/${BOARD}/latest-canary/test

17:00:43: NOTICE: Preparing to update the remote device ${IP}
17:00:48: ERROR: Device update failed.
17:00:48: ERROR: cros flash failed before completing.
17:00:48: ERROR: Failed to find most recent builds at gs://chromeos-releases/canary-channel/${BOARD}/

BUG=chromium:645049
TEST=cros flash ${IP} xbuddy://remote/${BOARD}/latest-canary/test

Change-Id: Ifdde06fbdc2c9ad95a2c4f12f534f98e18aff05d
Reviewed-on: https://chromium-review.googlesource.com/383091
Commit-Ready: Nicolas Boichat <drinkcat@chromium.org>
Tested-by: Daniel Kurtz <djkurtz@chromium.org>
Reviewed-by: Kuang-che Wu <kcwu@chromium.org>
diff --git a/gsutil_util.py b/gsutil_util.py
index 353c2f7..c3fdb9a 100644
--- a/gsutil_util.py
+++ b/gsutil_util.py
@@ -201,7 +201,7 @@
     The most recent version number found.
 
   """
-  cmd = 'gsutil ls -d %s' % gsutil_dir
+  cmd = 'gsutil ls %s' % gsutil_dir
   msg = 'Failed to find most recent builds at %s' % gsutil_dir
   dir_names = [p.split('/')[-2] for p in GSUtilRun(cmd, msg).splitlines()]
   try: