GCThing: js::gc::Cell
  which is annotated as a GCThing
GCThing: JustACell
  inherits from js::gc::Cell
    which is annotated as a GCThing
GCThing: JSObject
  inherits from js::gc::Cell
    which is annotated as a GCThing
GCThing: SpecialObject
  inherits from JSObject
    inherits from js::gc::Cell
      which is annotated as a GCThing
GCPointer: UnrootedPointer
  contains field 'obj' pointing to type JSObject
    inherits from js::gc::Cell
      which is annotated as a GCThing
