[analyzer] Add missing state transition in IteratorChecker.

After cleaning up program state maps in `checkDeadSymbols()`,
a transition should be added to generate the new state.

Differential Revision: https://reviews.llvm.org/D47417

llvm-svn: 338263

clang/lib/StaticAnalyzer/Checkers/IteratorChecker.cpp

@@ -551,6 +551,8 @@ void IteratorChecker::checkDeadSymbols(SymbolReaper &SR,
       State = State->remove<IteratorComparisonMap>(Comp.first);
     }
   }
+
+  C.addTransition(State);
 }
 
 ProgramStateRef IteratorChecker::evalAssume(ProgramStateRef State, SVal Cond,