NamespaceId as MosaicId in transaction

[decentraliser]

1. Expected behaviour and actual behaviour.
   MosaicId to be a NamespaceId

2. Steps to reproduce the problem.
   On a fresh catapult-bootstrap, query an initial harvester address with AccountHttp.transactions, and check the first one

The 2 mosaics are indicated as mosaicId

Now, if you use these ids to do a getNamespace, it will work:

new NamespaceHttp('http://fenix.nemesis.land:3000')
    .getNamespace(new NamespaceId([3294802500, 2243684972])).toPromise()

If you try this Id in a getMosaic, it will throw an unreadable error ([object][Object])

new MosaicHttp('http://fenix.nemesis.land:3000')
  .getMosaic(new MosaicId('85BBEA6CC462B244')).toPromise()

3. Specifications like the version of the project, operating system, or hardware.
   tech-bureau catapult-bootstrap latest, default config