Fix bug at mediation with old client

If dispute opener is old client the delayed payout tx is not sent in mediation case (only in refund agent cases).
At 1.4.0 we send it as well in mediation case and the mediator get a warning shown in case its missing.
To avoid that warning we check if dispute is of refund agent type and only check in that case.
This can be removed once we have enforced update to 1.4.0 (segwit will require that).
Also added checks to not add null entries in the duplicates checks.

core/src/main/java/bisq/core/support/dispute/Dispute.java

@@ -103,7 +103,7 @@ public final class Dispute implements NetworkPayload, PersistablePayload {
     @Nullable
     private String delayedPayoutTxId;
 
-    // Added at v1.3.9
+    // Added at v1.4.0
     @Setter
     @Nullable
     private String donationAddressOfDelayedPayoutTx;

core/src/main/java/bisq/core/trade/TradeDataValidation.java

@@ -20,6 +20,7 @@ package bisq.core.trade;
 import bisq.core.btc.wallet.BtcWalletService;
 import bisq.core.dao.DaoFacade;
 import bisq.core.offer.Offer;
+import bisq.core.support.SupportType;
 import bisq.core.support.dispute.Dispute;
 import bisq.core.util.validation.RegexValidatorFactory;
 
@@ -136,14 +137,18 @@ public class TradeDataValidation {
             set.add(uid);
 
             String delayedPayoutTxId = dispute.getDelayedPayoutTxId();
+            if (delayedPayoutTxId != null) {
                 disputesPerDelayedPayoutTxId.putIfAbsent(delayedPayoutTxId, new HashSet<>());
                 set = disputesPerDelayedPayoutTxId.get(delayedPayoutTxId);
                 set.add(uid);
+            }
 
             String depositTxId = dispute.getDepositTxId();
+            if (depositTxId != null) {
                 disputesPerDepositTxId.putIfAbsent(depositTxId, new HashSet<>());
                 set = disputesPerDepositTxId.get(depositTxId);
                 set.add(uid);
+            }
         });
 
         return new Tuple3<>(disputesPerTradeId, disputesPerDelayedPayoutTxId, disputesPerDepositTxId);
@@ -161,8 +166,14 @@ public class TradeDataValidation {
             String disputeToTestDepositTxId = disputeToTest.getDepositTxId();
             String disputeToTestUid = disputeToTest.getUid();
 
+            // For pre v1.4.0 we do not get the delayed payout tx sent in mediation cases but in refund agent case we do.
+            // So until all users have updated to 1.4.0 we only check in refund agent case. With 1.4.0 we send the
+            // delayed payout tx also in mediation cases and that if check can be removed.
+            if (disputeToTest.getSupportType() == SupportType.REFUND) {
                 checkNotNull(disputeToTestDelayedPayoutTxId,
-                    "delayedPayoutTxId must not be null. Trade ID: " + disputeToTestTradeId);
+                        "Delayed payout transaction ID is null. " +
+                                "Trade ID: " + disputeToTestTradeId);
+            }
             checkNotNull(disputeToTestDepositTxId,
                     "depositTxId must not be null. Trade ID: " + disputeToTestTradeId);
             checkNotNull(disputeToTestUid,
@@ -171,12 +182,16 @@ public class TradeDataValidation {
             checkArgument(disputesPerTradeId.get(disputeToTestTradeId).size() <= 2,
                     "We found more then 2 disputes with the same trade ID. " +
                             "Trade ID: " + disputeToTestTradeId);
+            if (!disputesPerDelayedPayoutTxId.isEmpty()) {
                 checkArgument(disputesPerDelayedPayoutTxId.get(disputeToTestDelayedPayoutTxId).size() <= 2,
                         "We found more then 2 disputes with the same delayedPayoutTxId. " +
                                 "Trade ID: " + disputeToTestTradeId);
+            }
+            if (!disputesPerDepositTxId.isEmpty()) {
                 checkArgument(disputesPerDepositTxId.get(disputeToTestDepositTxId).size() <= 2,
                         "We found more then 2 disputes with the same depositTxId. " +
                                 "Trade ID: " + disputeToTestTradeId);
+            }
 
         } catch (IllegalArgumentException | NullPointerException e) {
             throw new DisputeReplayException(disputeToTest, e.getMessage());