autotest: change db metric to match other names

Also some whitespace cleanup.

BUG=chromium:810966
TEST=None

Change-Id: I35e02da58ee5dae7834c589433c8db5a8b08228c
Reviewed-on: https://chromium-review.googlesource.com/1016169
Commit-Ready: Jacob Kopczynski <jkop@chromium.org>
Tested-by: Jacob Kopczynski <jkop@chromium.org>
Reviewed-by: Paul Hobbs <phobbs@google.com>
Reviewed-by: Dan Shi <dshi@google.com>
diff --git a/site_utils/check_slave_db_delay.py b/site_utils/check_slave_db_delay.py
index db76ddc..0e29523 100755
--- a/site_utils/check_slave_db_delay.py
+++ b/site_utils/check_slave_db_delay.py
@@ -32,7 +32,7 @@
 # SQL command to remove old test results in TKO database.
 SLAVE_STATUS_CMD = 'show slave status\G'
 DELAY_TIME_REGEX = 'Seconds_Behind_Master:\s(\d+)'
-DELAY_METRICS = 'chromeos/autotest/database/seconds_behind_master'
+DELAY_METRICS = 'chromeos/autotest/afe_db/seconds_behind_master'
 # A large delay to report to metrics indicating the replica is in error.
 LARGE_DELAY = 1000000