The 'numCollections' field in dbHash's response doesn't necessarily match the collection list that's returned because it a) doesn't factor in the filtering of system collections and b) it doesn't factor in the 'collections' filter list that the command can take.

We should remove the numCollections field from the response (src/mongo/db/commands/dbhash.cpp) and update the JS tests that reference it (jstests/sharding/sync_cluster_config/sync2.js and jstests/concurrency/fsm_libs/cluster.js).