Bug 1101525 - [Rooms] Create basic 'detail' panel given a room. r=crdlc

this return does not make sense, we can use an else statement thought

```js
if (_isOwner) {
  _ownerUI.textContent = _('createdByYou');
} else {
  navigator.mozL10n.localize(_ownerUI, 'createdBy', {
    owner: _room.roomOwner
  });
}