Modify stateful update clobber logic to write to different file.

We no longer want to use clobber-state because /usr/local and /var may have too much data to fit into /tmp.  This change has .stateful_update maintain all state rather than the factory file.

Change-Id: Ia4fad0395adc5709b84d96a1aef35b88e729fac6

TEST=Ran in a vm w/ and w/out setting stateful_update file to clean

Review URL:
1 file changed