Properly handle unsupported policies in tryProvision

* During the ICS timeframe, we added the ability to send back a
  list of unsupported policies in canProvision().  This change
  allows canProvision() to return a Policy even when it's not
* The code in tryProvision(), however, wasn't changed to reflect
  this, so it "passes" policies that aren't supportable
* The simple fix is to test whether the Policy is supportable
  in tryProvision
* Also added some logging

Change-Id: I14613e26a0306cab61ac263071e5b6ee19ebe43d
1 file changed