Maybe fix issue #5405788: Device continuously opening and closing...

...the "Complete action using" dialog

I have never been able to reproduce this consistently, but here is
another stab in the twilight.  It looks like during boot we have
a potential race where we could reset the config sequence number after
we had gone through a config change, causing ActivityThread to ignore
a following config change.  Maybe this change will help.

Change-Id: I4b731df5fd5c63894ca2e9bd34693b31ab1c0565