UpdateLifecycleImpl can return empty collectionMetadata even if ns is sharded

var config = {                                              

        mongos: 2,                                          

        shards: 2,                                          

        other: {                                            

            rs: true,                                      

            mongosOptions: { binVersion: "2.8"},       

            configOptions: { binVersion: oldVersion},       

            rsOptions: {binVersion: ["2.6"], nodes:3}

        }                                                                       

    };                                                      

assert.writeError(coll.update( value, Object.merge( value, { i : [ 3 ] } ) ));