Allow soft failures at runtime and fix null referrer for ICCE and NSME.

Change-Id: I814369f4e41cebf37007cb514a8bf19cbaf17e94
diff --git a/src/verifier/method_verifier.h b/src/verifier/method_verifier.h
index 273552d..3e3154b 100644
--- a/src/verifier/method_verifier.h
+++ b/src/verifier/method_verifier.h
@@ -659,6 +659,7 @@
 
   friend struct art::ReferenceMap2Visitor; // for VerifyMethodAndDump
 };
+std::ostream& operator<<(std::ostream& os, const MethodVerifier::FailureKind& rhs);
 
 }  // namespace verifier
 }  // namespace art