features/snapview-server: verify the fs instance in revalidated lookups as well

Change-Id: I691635e60aba72642c3c79d7da472884f1228301
BUG: 1158791
Reviewed-on: http://review.gluster.org/9008
Tested-by: Gluster Build System <jenkins@build.gluster.com>
Reviewed-by: Vijay Bellur <vbellur@redhat.com>