The following revision refers to this bug:
  https://chromium.googlesource.com/chromium/src.git/+/3865a3a561da35698827412be23a0905c9bd1594

commit 3865a3a561da35698827412be23a0905c9bd1594
Author: Henrique Ferreiro <hferreiro@igalia.com>
Date: Thu Jan 10 13:51:49 2019

Port SyncEncryptionPassphraseCollectionViewController away from PO2TS

SyncEncryptionPassphraseCollectionViewController is updated to use
IdentityManagerObserverBridge instead of ProfileOAuth2TokenService.

Bug:  913924 
Change-Id: I70d23e74d922105191f93bbd3cf3ba72c737a4a3
Reviewed-on: https://chromium-review.googlesource.com/c/1395027
Commit-Queue: Henrique Ferreiro <hferreiro@igalia.com>
Reviewed-by: David Roger <droger@chromium.org>
Reviewed-by: Sylvain Defresne <sdefresne@chromium.org>
Reviewed-by: Colin Blundell <blundell@chromium.org>
Cr-Commit-Position: refs/heads/master@{#621567}
[modify] https://crrev.com/3865a3a561da35698827412be23a0905c9bd1594/ios/chrome/browser/ui/settings/sync_encryption_passphrase_table_view_controller.mm