validation: Remove global ::ActivateBestChain

Instead use CChainState::ActivateBestChain, which is what the global one
calls anyway.

src/net_processing.cpp

@@ -1700,7 +1700,7 @@ void static ProcessGetBlockData(CNode& pfrom, Peer& peer, const CChainParams& ch
     } // release cs_main before calling ActivateBestChain
     if (need_activate_chain) {
         BlockValidationState state;
-        if (!ActivateBestChain(state, chainparams, a_recent_block)) {
+        if (!::ChainstateActive().ActivateBestChain(state, chainparams, a_recent_block)) {
             LogPrint(BCLog::NET, "failed to activate chain (%s)\n", state.ToString());
         }
     }
@@ -2960,7 +2960,7 @@ void PeerManagerImpl::ProcessMessage(CNode& pfrom, const std::string& msg_type,
                 a_recent_block = most_recent_block;
             }
             BlockValidationState state;
-            if (!ActivateBestChain(state, m_chainparams, a_recent_block)) {
+            if (!::ChainstateActive().ActivateBestChain(state, m_chainparams, a_recent_block)) {
                 LogPrint(BCLog::NET, "failed to activate chain (%s)\n", state.ToString());
             }
         }

src/rpc/blockchain.cpp

@@ -1603,7 +1603,7 @@ static RPCHelpMan invalidateblock()
     InvalidateBlock(state, Params(), pblockindex);
 
     if (state.IsValid()) {
-        ActivateBestChain(state, Params());
+        ::ChainstateActive().ActivateBestChain(state, Params());
     }
 
     if (!state.IsValid()) {
@@ -1643,7 +1643,7 @@ static RPCHelpMan reconsiderblock()
     }
 
     BlockValidationState state;
-    ActivateBestChain(state, Params());
+    ::ChainstateActive().ActivateBestChain(state, Params());
 
     if (!state.IsValid()) {
         throw JSONRPCError(RPC_DATABASE_ERROR, state.ToString());

src/test/util/setup_common.cpp

@@ -185,7 +185,7 @@ TestingSetup::TestingSetup(const std::string& chainName, const std::vector<const
     }
 
     BlockValidationState state;
-    if (!ActivateBestChain(state, chainparams)) {
+    if (!::ChainstateActive().ActivateBestChain(state, chainparams)) {
         throw std::runtime_error(strprintf("ActivateBestChain failed. (%s)", state.ToString()));
     }
 

src/validation.cpp

@@ -2899,10 +2899,6 @@ bool CChainState::ActivateBestChain(BlockValidationState &state, const CChainPar
     return true;
 }
 
-bool ActivateBestChain(BlockValidationState &state, const CChainParams& chainparams, std::shared_ptr<const CBlock> pblock) {
-    return ::ChainstateActive().ActivateBestChain(state, chainparams, std::move(pblock));
-}
-
 bool CChainState::PreciousBlock(BlockValidationState& state, const CChainParams& params, CBlockIndex *pindex)
 {
     {
@@ -4681,7 +4677,7 @@ void LoadExternalBlockFile(const CChainParams& chainparams, FILE* fileIn, FlatFi
                 // Activate the genesis block so normal node progress can continue
                 if (hash == chainparams.GetConsensus().hashGenesisBlock) {
                     BlockValidationState state;
-                    if (!ActivateBestChain(state, chainparams, nullptr)) {
+                    if (!::ChainstateActive().ActivateBestChain(state, chainparams, nullptr)) {
                         break;
                     }
                 }

src/validation.h

@@ -167,13 +167,6 @@ void StopScriptCheckWorkerThreads();
  * @returns                    The tx if found, otherwise nullptr
  */
 CTransactionRef GetTransaction(const CBlockIndex* const block_index, const CTxMemPool* const mempool, const uint256& hash, const Consensus::Params& consensusParams, uint256& hashBlock);
-/**
- * Find the best known block, and make it the tip of the block chain
- *
- * May not be called with cs_main held. May not be called in a
- * validationinterface callback.
- */
-bool ActivateBestChain(BlockValidationState& state, const CChainParams& chainparams, std::shared_ptr<const CBlock> pblock = std::shared_ptr<const CBlock>());
 CAmount GetBlockSubsidy(int nHeight, const Consensus::Params& consensusParams);
 
 /** Guess verification progress (as a fraction between 0.0=genesis and 1.0=current tip). */
@@ -648,6 +641,8 @@ public:
     void PruneAndFlush();
 
     /**
+     * Find the best known block, and make it the tip of the block chain
+     *
      * Make the best chain active, in multiple steps. The result is either failure
      * or an activated best chain. pblock is either nullptr or a pointer to a block
      * that is already loaded (to avoid loading it again from disk).
@@ -664,7 +659,7 @@ public:
     bool ActivateBestChain(
         BlockValidationState& state,
         const CChainParams& chainparams,
-        std::shared_ptr<const CBlock> pblock) LOCKS_EXCLUDED(cs_main);
+        std::shared_ptr<const CBlock> pblock = nullptr) LOCKS_EXCLUDED(cs_main);
 
     bool AcceptBlock(const std::shared_ptr<const CBlock>& pblock, BlockValidationState& state, const CChainParams& chainparams, CBlockIndex** ppindex, bool fRequested, const FlatFilePos* dbp, bool* fNewBlock) EXCLUSIVE_LOCKS_REQUIRED(cs_main);