Degrade: Fix smart sync/smart tag

This was broken in b2bd91c9, which updated the manifest after it had
been overridden, which made it fall back to the original file (and
not the one from the manifest server).

This builds on 07669002 and overrides the manifest by the one
downloaded from the manifest server completely.

Change-Id: Ic3972390a68919b614616631d99c9e7a63c0e0db