That is inherited from chrome side code. It is not ideal that OnActiveUserSessionChanged fires at different stage for primary (1st) user (no user profile) and secondary users (user profile loaded). I think almost all code expects the user profile is loaded when getting this notification. Having no user profile is a bit unexpected and wait for an additional notification makes code difficult to write.

For short term fix, I will put in a work around for ash to defer primary user's notification until user profile is loaded.

For longer term, I will include this case during the UserManager/SessionManager refactoring and update chrome side code as well.

The following revision refers to this bug:
  https://chromium.googlesource.com/chromium/src.git/+/4cfa57df48555a9f2f54d2f5cb78a3db29b3b187

commit 4cfa57df48555a9f2f54d2f5cb78a3db29b3b187
Author: xiyuan <xiyuan@chromium.org>
Date: Mon May 08 18:04:56 2017

cros: Defer primary user meta update until active

Defer the meta/order update to ash until session state becomes
active for primary user. So that ash side code could be simplified
to expect having a consistent state for both primary user session
and secondary user sessions.

BUG= 718458 

Review-Url: https://codereview.chromium.org/2863993002
Cr-Commit-Position: refs/heads/master@{#470048}

[modify] https://crrev.com/4cfa57df48555a9f2f54d2f5cb78a3db29b3b187/chrome/browser/ui/ash/session_controller_client.cc
[modify] https://crrev.com/4cfa57df48555a9f2f54d2f5cb78a3db29b3b187/chrome/browser/ui/ash/session_controller_client_unittest.cc