gooftool: Turn off developer switch on finalization.

BUG=chrome-os-partner:10007
TEST=./gooftool verify_switch_dev

Change-Id: I1a89ac1924f787bdd49efba9acf22ba424ec3a8e
Reviewed-on: https://gerrit.chromium.org/gerrit/26910
Reviewed-by: Chinyue Chen <chinyue@chromium.org>
Commit-Ready: Hung-Te Lin <hungte@chromium.org>
Tested-by: Hung-Te Lin <hungte@chromium.org>
diff --git a/py/gooftool.py b/py/gooftool.py
index 4d33725..bf1def1 100755
--- a/py/gooftool.py
+++ b/py/gooftool.py
@@ -406,12 +406,12 @@
       raise Error, 'developer mode is enabled'
     else:
       return
-  # Try ChromeOS-EC. This may hang 15 seconds if the EC does not respond.
-  logging.warn('VerifyDevSwitch: Trying ChromeOS-EC...')
-  if not Shell('ectool vboot 0').success:
+  # devsw_cur is not available -- probably a device using keyboard-based
+  # developer/recovery mode.  We can't verify this until next reboot, because
+  # the real values are stored in TPM.
+  logging.warn('VerifyDevSwitch: Trying disable_dev_request...')
+  if not Shell('crossystem disable_dev_request=1').success:
     raise Error, 'failed to turn off developer mode.'
-  # TODO(hungte) Verify if the switch is turned off properly, using "ectoo
-  # vboot" and parse the key-value pairs, when the names are determined.
 
 
 @Command('write_protect')