This removes the passphrase migration and fixes the passphrase backups. Users will be able to select the passphrase backup (learningmachine.dat) file from their device themselves in Android 11+. For Android 6.0+, we'll do our best to access what was previously the default storage location for learningmachine.dat. If we can't access it programmatically, then we'll prompt the user to select the backup file themselves from the device. For Android <6.0, we'll always access the default location, and the user won't be prompted to choose the file.
This removes the passphrase migration and fixes the passphrase backups. Users will be able to select the passphrase backup (learningmachine.dat) file from their device themselves in Android 11+. For Android 6.0+, we'll do our best to access what was previously the default storage location for learningmachine.dat. If we can't access it programmatically, then we'll prompt the user to select the backup file themselves from the device. For Android <6.0, we'll always access the default location, and the user won't be prompted to choose the file.