Regenerate user 0's CE key when needed

Try to be more robust in the case where the device is rebooted during
the first boot, in between the generation and the storage of user 0's CE
key.  We can automatically recover from this scenario by generating a
new CE key and replacing /data/data.

This might resolve b/251213447.

Bug: 232452368
Bug: 251213447
Ignore-AOSP-First: depends on other changes in internal master
Change-Id: If0675de9167f7f855c0c0c6afe55fd1da39f5ce1
1 file changed