New user type introduced. Combines regular and supervised features.
BUG=419009

Inherited from initial CL https://chromereviews.googleplex.com/100407014/

TBR=oshima@chromium.org, achuithb@chromium.org, Finnur@chromium.org, xiyuan@chromium.org, jennyz@chromium.org, bartfab@chromium.org

Review URL: https://codereview.chromium.org/718673002

Cr-Commit-Position: refs/heads/master@{#304398}
29 files changed