Password change warning should be updated for e2e key backup

[lampholder]

[lampholder]

How about:

You could lose your encrypted messages!

Changing your password will sign out all of your signed-in devices. If you haven't enabled Key Backup on all of your devices, those devices will lose their encryption keys unless you export them manually. This could make your encrypted messages unreadable.

If key backup is not enabled on this device: [ Cancel ] [ Start using Key Backup ] [ Export E2E room keys ] [ Continue ]
If key backup is enabled on this device: [ Cancel ] [ Continue ]

[benqrn]

If Key Backup is enabled and verifiably up to date, a much less scary dialog should be presented, so users can confidently change their password without having doubt that they will lose access to messages.