Add account_id to signin manager notifications.

BUG=341408
TBR=TBR=bauerb@chromium.org, benwells@chromium.org, gene@chromium.org, asvitkine@chromium.org, noms@chromium.org, tim@chromium.org, sky@chromium.org, fgorski@chromium.org

Review URL: https://codereview.chromium.org/502343002

Cr-Commit-Position: refs/heads/master@{#292635}
41 files changed