Remove fUseWTXID parameter from CBlockHeaderAndShortTxIDs constructor

All uses of CBlockHeaderAndShortTxIDs in the product code are
constructed with fUseWTXID=true, so remove the parameter.

There is one use of the CBlockHeaderAndShortTxIDs constructor with
fUseWTXID=false in the unit tests. This is used to construct a
CBlockHeaderAndShortTxIDs for a block with only the coinbase
transaction, so setting fUseWTXID to true or false makes no difference.

Suggested in bitcoin/bitcoin#20799 (review)

Author: jnewbery

src/blockencodings.cpp

@@ -16,15 +16,15 @@
 
 #include <unordered_map>
 
-CBlockHeaderAndShortTxIDs::CBlockHeaderAndShortTxIDs(const CBlock& block, bool fUseWTXID) :
+CBlockHeaderAndShortTxIDs::CBlockHeaderAndShortTxIDs(const CBlock& block) :
         nonce(GetRand<uint64_t>()),
         shorttxids(block.vtx.size() - 1), prefilledtxn(1), header(block) {
     FillShortTxIDSelector();
     //TODO: Use our mempool prior to block acceptance to predictively fill more than just the coinbase
     prefilledtxn[0] = {0, block.vtx[0]};
     for (size_t i = 1; i < block.vtx.size(); i++) {
         const CTransaction& tx = *block.vtx[i];
-        shorttxids[i - 1] = GetShortID(fUseWTXID ? tx.GetWitnessHash() : tx.GetHash());
+        shorttxids[i - 1] = GetShortID(tx.GetWitnessHash());
     }
 }
 

src/blockencodings.h

@@ -104,7 +104,7 @@ class CBlockHeaderAndShortTxIDs {
     // Dummy for deserialization
     CBlockHeaderAndShortTxIDs() {}
 
-    CBlockHeaderAndShortTxIDs(const CBlock& block, bool fUseWTXID);
+    CBlockHeaderAndShortTxIDs(const CBlock& block);
 
     uint64_t GetShortID(const uint256& txhash) const;
 

src/net_processing.cpp

@@ -1632,7 +1632,7 @@ void PeerManagerImpl::BlockDisconnected(const std::shared_ptr<const CBlock> &blo
  */
 void PeerManagerImpl::NewPoWValidBlock(const CBlockIndex *pindex, const std::shared_ptr<const CBlock>& pblock)
 {
-    std::shared_ptr<const CBlockHeaderAndShortTxIDs> pcmpctblock = std::make_shared<const CBlockHeaderAndShortTxIDs> (*pblock, true);
+    auto pcmpctblock = std::make_shared<const CBlockHeaderAndShortTxIDs>(*pblock);
     const CNetMsgMaker msgMaker(PROTOCOL_VERSION);
 
     LOCK(cs_main);
@@ -1978,7 +1978,7 @@ void PeerManagerImpl::ProcessGetBlockData(CNode& pfrom, Peer& peer, const CInv&
                 if (a_recent_compact_block && a_recent_compact_block->header.GetHash() == pindex->GetBlockHash()) {
                     m_connman.PushMessage(&pfrom, msgMaker.Make(NetMsgType::CMPCTBLOCK, *a_recent_compact_block));
                 } else {
-                    CBlockHeaderAndShortTxIDs cmpctblock(*pblock, true);
+                    CBlockHeaderAndShortTxIDs cmpctblock{*pblock};
                     m_connman.PushMessage(&pfrom, msgMaker.Make(NetMsgType::CMPCTBLOCK, cmpctblock));
                 }
             } else {
@@ -4771,7 +4771,7 @@ bool PeerManagerImpl::SendMessages(CNode* pto)
                         CBlock block;
                         bool ret = ReadBlockFromDisk(block, pBestIndex, consensusParams);
                         assert(ret);
-                        CBlockHeaderAndShortTxIDs cmpctblock(block, true);
+                        CBlockHeaderAndShortTxIDs cmpctblock{block};
                         m_connman.PushMessage(pto, msgMaker.Make(NetMsgType::CMPCTBLOCK, cmpctblock));
                     }
                     state.pindexBestHeaderSent = pBestIndex;

src/test/blockencodings_tests.cpp

@@ -64,7 +64,7 @@ BOOST_AUTO_TEST_CASE(SimpleRoundTripTest)
 
     // Do a simple ShortTxIDs RT
     {
-        CBlockHeaderAndShortTxIDs shortIDs(block, true);
+        CBlockHeaderAndShortTxIDs shortIDs{block};
 
         CDataStream stream(SER_NETWORK, PROTOCOL_VERSION);
         stream << shortIDs;
@@ -122,7 +122,7 @@ class TestHeaderAndShortIDs {
         stream >> *this;
     }
     explicit TestHeaderAndShortIDs(const CBlock& block) :
-        TestHeaderAndShortIDs(CBlockHeaderAndShortTxIDs(block, true)) {}
+        TestHeaderAndShortIDs(CBlockHeaderAndShortTxIDs{block}) {}
 
     uint64_t GetShortID(const uint256& txhash) const {
         CDataStream stream(SER_NETWORK, PROTOCOL_VERSION);
@@ -279,7 +279,7 @@ BOOST_AUTO_TEST_CASE(EmptyBlockRoundTripTest)
 
     // Test simple header round-trip with only coinbase
     {
-        CBlockHeaderAndShortTxIDs shortIDs(block, false);
+        CBlockHeaderAndShortTxIDs shortIDs{block};
 
         CDataStream stream(SER_NETWORK, PROTOCOL_VERSION);
         stream << shortIDs;