Do not populate indexDetails for mobile storage engine

python buildscripts\resmoke.py --suites=core --mongod=./mongoe jstests/core/apitest_dbcollection.js

2018-04-19T16:44:24.586-0400 E QUERY    [js] Error: [0] != [0] are equal : a_1 exists in indexDetails but contains no information: {

    "ns" : "test.apttest_dbcollection",

    "size" : 33,

    "count" : 1,

    "avgObjSize" : 33,

    "storageSize" : 33,

    "capped" : false,

    "nindexes" : 2,

    "indexDetails" : {

            "a_1" : {

            }

    },

    "totalIndexSize" : 22,

    "indexSizes" : {

            "_id_" : 16,

            "a_1" : 6

    },

    "ok" : 1

} :

doassert@src/mongo/shell/assert.js:18:14

assert.neq@src/mongo/shell/assert.js:207:9

checkIndexDetails@.\jstests\core\apitest_dbcollection.js:217:1

@.\jstests\core\apitest_dbcollection.js:226:1

@.\jstests\core\apitest_dbcollection.js:151:2