Fetch account info from LDAP if session email address not exist
|Reported by:||Jiang Xin||Owned by:||Jiang Xin|
To make less LDAP query, we only do ldap bind and query if page is redirect from CoSign SSO page.
But what if user login from CoSign SSO first, and visit trac latter. At this circumstance, no redirect occur, and user email address not set by default.