Merge #11406: Add state message print to AcceptBlock failure message.

6643b80 Add state message print to AcceptBlock failure message. (Matt Corallo)

Pull request description:

  This should make it easier to debug issues where the CheckBlock at
  the top of ProcessNewBlock fails (which does not print, in contrast
  to AcceptBlock, which always prints).

  This was motivated by #11371 which appears to be exactly such a case, and is not debuggable from the information provided. Not sure how much this would have helped in that case, but it is kinda weird that we can reject a block without ever printing why.

Tree-SHA512: 7a1c2c76080b810212da885c38e091609e409c62918cc326bb36a1096e09b2ae7e26fd4bdaefd79863d2894e2823e463005700a524940f177a59ef09f589b2f1

src/validation.cpp

@@ -3192,7 +3192,7 @@ bool ProcessNewBlock(const CChainParams& chainparams, const std::shared_ptr<cons
         CheckBlockIndex(chainparams.GetConsensus());
         if (!ret) {
             GetMainSignals().BlockChecked(*pblock, state);
-            return error("%s: AcceptBlock FAILED", __func__);
+            return error("%s: AcceptBlock FAILED (%s)", __func__, state.GetDebugMessage());
         }
     }