gatekeeper_ng: Always update database after close.
gatekeeper_ng: Always update database after close.

'gatekeeper_ng' has e-mail notifications in its critical path before
database update. As a result, if the e-mail notification fail,
Gatekeeper doesn't update its DB.

If it closes the tree but doesn't send an e-mail, this will cause
Gatekeeper to spam tree closures indefinitely.

BUG=None
TEST=None

Review URL: https://codereview.chromium.org/1028753002

git-svn-id: 239fca9b83025a0b6f823aeeca02ba5be3d9fd76@294519 0039d316-1c4b-4281-b951-d872f2087c98

eunchong/build,eunchong/build,eunchong/build,eunchong/build