public boolean isDeleted(Lock lock) {
		return deleted || !validate(lock);
	}
Returns true if this object has been deleted. Note: once an object has been deleted, it will
never be "refreshed". For example, if an object is ever deleted and is resurrected via an
"undo", you will have get a fresh instance of the object.

@param lock object cache lock object
@return true if this object has been deleted.
Ghidra/Framework/SoftwareModeling/src/main/java/ghidra/program/database/DatabaseObject.java