GitLab

Remove all references of ACCOUNT_TYPE_SESSIONLESS_USER from
SessionManagerClient, in preparation of removing this account type from
session_manager.
The only user of this account type was PreSigninPolicyFetcher which was
removed in CL:2513205

Bug: 832127
Change-Id: I3b8e8a9fdfb38c5cc925a1c77dafc3a96297b054
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/2513584
Commit-Queue: Pavol Marko <pmarko@chromium.org>
Reviewed-by: Achuith Bhandarkar <achuith@chromium.org>
Cr-Commit-Position: refs/heads/master@{#836801}