refactor: move CInstantSendManager::PreVerifyInstantSendLock into CIn stantSendLock::TriviallyValid (#5102)

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src/llmq/instantsend.cpp

@@ -787,7 +787,7 @@ void CInstantSendManager::ProcessMessageInstantSendLock(const CNode* pfrom, cons
         fDIP0024IsActive = utils::IsDIP0024Active(::ChainActive().Tip());
     }
 
-    if (!PreVerifyInstantSendLock(*islock)) {
+    if (!islock->TriviallyValid()) {
         LOCK(cs_main);
         Misbehaving(pfrom->GetId(), 100);
         return;
@@ -830,18 +830,17 @@ void CInstantSendManager::ProcessMessageInstantSendLock(const CNode* pfrom, cons
 
 /**
  * Handles trivial ISLock verification
- * @param islock The islock message being undergoing verification
  * @return returns false if verification failed, otherwise true
  */
-bool CInstantSendManager::PreVerifyInstantSendLock(const llmq::CInstantSendLock& islock)
+bool CInstantSendLock::TriviallyValid() const
 {
-    if (islock.txid.IsNull() || islock.inputs.empty()) {
+    if (txid.IsNull() || inputs.empty()) {
         return false;
     }
 
     // Check that each input is unique
     std::set<COutPoint> dups;
-    for (const auto& o : islock.inputs) {
+    for (const auto& o : inputs) {
         if (!dups.emplace(o).second) {
             return false;
         }

src/llmq/instantsend.h

@@ -58,6 +58,7 @@ struct CInstantSendLock
 
     uint256 GetRequestId() const;
     bool IsDeterministic() const { return nVersion != islock_version; }
+    bool TriviallyValid() const;
 };
 
 using CInstantSendLockPtr = std::shared_ptr<CInstantSendLock>;
@@ -280,7 +281,6 @@ private:
     void TrySignInstantSendLock(const CTransaction& tx) LOCKS_EXCLUDED(cs_creating);
 
     void ProcessMessageInstantSendLock(const CNode* pfrom, const CInstantSendLockPtr& islock);
-    static bool PreVerifyInstantSendLock(const CInstantSendLock& islock);
     bool ProcessPendingInstantSendLocks();
     bool ProcessPendingInstantSendLocks(bool deterministic) LOCKS_EXCLUDED(cs_pendingLocks);