From an email conversation:

"We may want to think about removing the log-out-on-lock-screen-crash behavior now. It'd probably be possible to add a flag to Chrome that session_manager can pass when restarting it to tell it to display the lock screen initially."

"I think the current behavior is mostly carried over from the pre-Ash days when we ran a separate process to display the lock screen -- if the lock program crashed, we wanted to make sure that Chrome wasn't exposed. Chrome already knows how to go directly into a user session at startup (e.g. for a flag change or when the browser crashes), so it seems reasonable to consider supporting going back to the login screen."

So if we did this, we'd probably add a --lock-screen or similar flag to Chrome that session_manager could pass if it wants Chrome to come up with the screen locked. session_manager already passes similar flags to Chrome in other situations (see --login-manager, --login-user, and --login-profile in BrowserJob::StartSession).

Jacob, assigning to you to get your thoughts about how feasible this would be to do on the Chrome side. I can help out with the session_manager side of it if we do it.