Autotest: Fix failure retrieving logs with rsync

BUG=chromium:343991
TEST=emerged

Change-Id: Icbd642a657e68e133fae20cb994330282382a6aa
Reviewed-on: https://chromium-review.googlesource.com/186660
Reviewed-by: Chris Sosa <sosa@chromium.org>
Reviewed-by: Gwendal Grignou <gwendal@chromium.org>
Commit-Queue: Gwendal Grignou <gwendal@chromium.org>
Tested-by: Gwendal Grignou <gwendal@chromium.org>
diff --git a/client/common_lib/cros/autoupdater.py b/client/common_lib/cros/autoupdater.py
index a2c65d8..453772b 100644
--- a/client/common_lib/cros/autoupdater.py
+++ b/client/common_lib/cros/autoupdater.py
@@ -22,7 +22,7 @@
 UPDATER_IDLE = 'UPDATE_STATUS_IDLE'
 UPDATER_NEED_REBOOT = 'UPDATE_STATUS_UPDATED_NEED_REBOOT'
 UPDATED_MARKER = '/var/run/update_engine_autoupdate_completed'
-UPDATER_LOGS = '/var/log/messages /var/log/update_engine'
+UPDATER_LOGS = ['/var/log/messages', '/var/log/update_engine']
 # A list of update engine client states that occur after an update is triggered.
 UPDATER_PROCESSING_UPDATE = ['UPDATE_STATUS_CHECKING_FORUPDATE',
                              'UPDATE_STATUS_UPDATE_AVAILABLE',