ignore fault on mailbox message task after shut down

Author: woodser

core/src/main/java/haveno/core/trade/protocol/tasks/SendMailboxMessageTask.java

@@ -82,6 +82,7 @@ public void onStoredInMailbox() {
 
                         @Override
                         public void onFault(String errorMessage) {
+                            if (processModel.getP2PService().isShutDownStarted()) return;
                             log.error("{} failed: Peer {}. tradeId={}, uid={}, errorMessage={}", message.getClass().getSimpleName(), peersNodeAddress, message.getOfferId(), message.getUid(), errorMessage);
                             SendMailboxMessageTask.this.onFault(errorMessage, message);
                         }

p2p/src/main/java/haveno/network/p2p/P2PService.java

@@ -109,6 +109,8 @@ public class P2PService implements SetupListener, MessageListener, ConnectionLis
 
     @Getter
     private static NodeAddress myNodeAddress;
+    @Getter
+    private boolean isShutDownStarted = false;
 
 
     ///////////////////////////////////////////////////////////////////////////////////////////
@@ -192,6 +194,7 @@ public void shutDown(Runnable shutDownCompleteHandler) {
 
     private void doShutDown() {
         log.info("P2PService doShutDown started");
+        isShutDownStarted = true;
 
         if (p2PDataStorage != null) {
             p2PDataStorage.shutDown();