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Returns the ACL for the node responsible for the given node's permissions. Note: In the following example, 'resourceId' is the id of the node to which permissions are attached, either rid or one of rid's ancestors; there is one 'resourceAccess' entry per UserGroup (aka 'principal') having access to the resource; 'userGroupId' is the id of the UserGroup object; 'accessType' is the list of types of access the given UserGroup has to the given resource.
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Note: This is only used when a "resourceId" already specifies it's its access control list (does not inherit from an ancestor).
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