Dependency graph used by agnostic excludes positive literals
of type compile.Literal. But when a policy is deleted, the facts
in the policy are deleted as atomic rules of type compile.Rule. As
a result, some nodes in the dependency graph are prematurely deleted
because the deleting of facts (type compile.Rule) via policy delete
decreased ref counters that had not been correspondingly increased
by the adding of those same facts (type compile.Literal). When a
dependency graph is thus corrupted, congress gives Internal Server
Error on all future attempts to add/delete/sync rules.
This patch fixes the problem by having agnostic treat an atomic rule
(type compile.Rule) the same way it treats an atom
(type compile.Literal) in the dependency graph -- ignore both.
Closes-Bug: 1662809
Change-Id: I8080cbb7c375d90259f7b8a2a62d714ebe4aee5f
d635bad1ae