cacheBuildingData
Explicitly store a BuildingData instance in the Java-level cache so that subsequent calls to getCachedBuildingData return this object without going through the engine.
This is used by the plotProperty re-init path: after the engine has been primed via getBuildingData, the primed BuildingData is stored here so that the newly created PropertyLayers can retrieve it immediately from getCachedBuildingData.
Parameters
buildingId
the building whose data is being cached
data
the primed BuildingData to store (must not be null)