[refactor] drop IsInvalid(nDoSOut)

Co-authored-by: Anthony Towns <aj@erisian.com.au>

src/consensus/validation.h

@@ -71,13 +71,6 @@ public:
     bool IsError() const {
         return mode == MODE_ERROR;
     }
-    bool IsInvalid(int &nDoSOut) const {
-        if (IsInvalid()) {
-            nDoSOut = nDoS;
-            return true;
-        }
-        return false;
-    }
     bool CorruptionPossible() const {
         return corruptionPossible;
     }

src/test/txvalidation_tests.cpp

@@ -52,10 +52,6 @@ BOOST_FIXTURE_TEST_CASE(tx_mempool_reject_coinbase, TestChain100Setup)
     // Check that the validation state reflects the unsuccessful attempt.
     BOOST_CHECK(state.IsInvalid());
     BOOST_CHECK_EQUAL(state.GetRejectReason(), "coinbase");
-
-    int nDoS;
-    BOOST_CHECK_EQUAL(state.IsInvalid(nDoS), true);
-    BOOST_CHECK_EQUAL(nDoS, 100);
 }
 
 BOOST_AUTO_TEST_SUITE_END()