Merge changes from topic "unencrypted-dirs-q" into qt-dev
* changes:
[RESTRICT AUTOMERGE] Log to EventLog on prepareUserStorage failure
[RESTRICT AUTOMERGE] Ignore errors preparing user storage for existing users
[RESTRICT AUTOMERGE] UserDataPreparer: reboot to recovery for system user only
[RESTRICT AUTOMERGE] UserDataPreparer: reboot to recovery if preparing user storage fails
[RESTRICT AUTOMERGE] StorageManagerService: don't ignore failures to prepare user storage
Check user unlocked before write to /data/system_ce/0/snapshots