Should return stateNotNull.

git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@106741 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/lib/Checker/StreamChecker.cpp b/lib/Checker/StreamChecker.cpp
index 1bd43f3..8d123c1 100644
--- a/lib/Checker/StreamChecker.cpp
+++ b/lib/Checker/StreamChecker.cpp
@@ -258,5 +258,5 @@
     }
     return 0;
   }
-  return stateNull;
+  return stateNotNull;
 }