test: Add FakeNodeClock m_clock to TestChain100Setup

diff --git a/src/bench/index_blockfilter.cpp b/src/bench/index_blockfilter.cpp
index 781aa097..d813f1d3 100644
--- a/src/bench/index_blockfilter.cpp
+++ b/src/bench/index_blockfilter.cpp
@@ -38,10 +38,9 @@ static void BlockFilterIndexSync(benchmark::Bench& bench)
     CPubKey pubkey{"02ed26169896db86ced4cbb7b3ecef9859b5952825adbeab998fb5b307e54949c9"_hex_u8};
     CScript script = GetScriptForDestination(WitnessV0KeyHash(pubkey));
     std::vector<CMutableTransaction> noTxns;
-    FakeNodeClock clock{};
     for (int i = 0; i < CHAIN_SIZE - 100; i++) {
         test_setup->CreateAndProcessBlock(noTxns, script);
-        clock += 1s;
+        test_setup->m_clock += 1s;
     }
     assert(WITH_LOCK(::cs_main, return test_setup->m_node.chainman->ActiveHeight() == CHAIN_SIZE));
 
diff --git a/src/test/blockfilter_index_tests.cpp b/src/test/blockfilter_index_tests.cpp
index e9d9a409..a48a355d 100644
--- a/src/test/blockfilter_index_tests.cpp
+++ b/src/test/blockfilter_index_tests.cpp
@@ -21,11 +21,11 @@
 #include <test/util/blockfilter.h>
 #include <test/util/common.h>
 #include <test/util/setup_common.h>
+#include <test/util/time.h>
 #include <tinyformat.h>
 #include <uint256.h>
 #include <util/check.h>
 #include <util/fs.h>
-#include <util/time.h>
 #include <validation.h>
 
 #include <boost/test/unit_test.hpp>
@@ -332,14 +332,15 @@ BOOST_FIXTURE_TEST_CASE(blockfilter_index_init_destroy, BasicTestingSetup)
 class IndexReorgCrash : public BaseIndex
 {
 private:
+    FakeNodeClock& m_clock;
     std::unique_ptr<BaseIndex::DB> m_db;
     std::shared_future<void> m_blocker;
     int m_blocking_height;
 
 public:
     explicit IndexReorgCrash(std::unique_ptr<interfaces::Chain> chain, std::shared_future<void> blocker,
-                             int blocking_height) : BaseIndex(std::move(chain), "test index"), m_blocker(blocker),
-                                                    m_blocking_height(blocking_height)
+                             int blocking_height, FakeNodeClock& clock)
+        : BaseIndex(std::move(chain), "test index"), m_clock(clock), m_blocker(blocker), m_blocking_height(blocking_height)
     {
         const fs::path path = gArgs.GetDataDirNet() / "index";
         fs::create_directories(path);
@@ -356,7 +357,7 @@ public:
 
         // Move mock time forward so the best index gets updated only when we are not at the blocking height
         if (block.height == m_blocking_height - 1 || block.height > m_blocking_height) {
-            SetMockTime(GetTime<std::chrono::seconds>() + 31s);
+            m_clock += 31s;
         }
 
         return true;
@@ -365,14 +366,11 @@ public:
 
 BOOST_FIXTURE_TEST_CASE(index_reorg_crash, BuildChainTestingSetup)
 {
-    // Enable mock time
-    SetMockTime(GetTime<std::chrono::minutes>());
-
     std::promise<void> promise;
     std::shared_future<void> blocker(promise.get_future());
     int blocking_height = WITH_LOCK(cs_main, return m_node.chainman->ActiveChain().Tip()->nHeight);
 
-    IndexReorgCrash index(interfaces::MakeChain(m_node), blocker, blocking_height);
+    IndexReorgCrash index{interfaces::MakeChain(m_node), blocker, blocking_height, m_clock};
     BOOST_REQUIRE(index.Init());
     BOOST_REQUIRE(index.StartBackgroundSync());
 
diff --git a/src/test/chainstate_write_tests.cpp b/src/test/chainstate_write_tests.cpp
index 64a3fc1b..01e00011 100644
--- a/src/test/chainstate_write_tests.cpp
+++ b/src/test/chainstate_write_tests.cpp
@@ -70,7 +70,6 @@ BOOST_FIXTURE_TEST_CASE(write_during_multiblock_activation, TestChain100Setup)
 
     auto& chainstate{Assert(m_node.chainman)->ActiveChainstate()};
     BlockValidationState state_dummy{};
-    FakeNodeClock clock{};
 
     // Pop two blocks from the tip
     const CBlockIndex* tip{chainstate.m_chain.Tip()};
@@ -89,7 +88,7 @@ BOOST_FIXTURE_TEST_CASE(write_during_multiblock_activation, TestChain100Setup)
     m_node.validation_signals->SyncWithValidationInterfaceQueue();
     // The periodic flush interval is between 50 and 70 minutes (inclusive)
     // The next call to a PERIODIC write will flush
-    clock += DATABASE_WRITE_INTERVAL_MAX;
+    m_clock += DATABASE_WRITE_INTERVAL_MAX;
 
     const auto sub{std::make_shared<TestSubscriber>()};
     m_node.validation_signals->RegisterSharedValidationInterface(sub);
diff --git a/src/test/util/setup_common.cpp b/src/test/util/setup_common.cpp
index d7b7b29d..8097494d 100644
--- a/src/test/util/setup_common.cpp
+++ b/src/test/util/setup_common.cpp
@@ -416,7 +416,6 @@ TestChain100Setup::TestChain100Setup(
     TestOpts opts)
     : TestingSetup{ChainType::REGTEST, opts}
 {
-    SetMockTime(1598887952);
     constexpr std::array<unsigned char, 32> vchKey = {
         {0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 1}};
     coinbaseKey.Set(vchKey.begin(), vchKey.end(), true);
@@ -438,7 +437,7 @@ void TestChain100Setup::mineBlocks(int num_blocks)
     for (int i = 0; i < num_blocks; i++) {
         std::vector<CMutableTransaction> noTxns;
         CBlock b = CreateAndProcessBlock(noTxns, scriptPubKey);
-        SetMockTime(GetTime() + 1);
+        m_clock += 1s;
         m_coinbase_txns.push_back(b.vtx[0]);
     }
 }
diff --git a/src/test/util/setup_common.h b/src/test/util/setup_common.h
index 62bfaba9..72a3a620 100644
--- a/src/test/util/setup_common.h
+++ b/src/test/util/setup_common.h
@@ -14,6 +14,7 @@
 #include <primitives/transaction.h>
 #include <random.h>
 #include <test/util/random.h>
+#include <test/util/time.h>
 #include <util/chaintype.h> // IWYU pragma: export
 #include <util/fs.h>
 #include <util/signalinterrupt.h>
@@ -226,6 +227,7 @@ struct TestChain100Setup : public TestingSetup {
      */
     std::vector<CTransactionRef> PopulateMempool(FastRandomContext& det_rand, size_t num_transactions, bool submit);
 
+    FakeNodeClock m_clock{std::chrono::seconds{1598887952}};
     std::vector<CTransactionRef> m_coinbase_txns; // For convenience, coinbase transactions
     CKey coinbaseKey; // private/public key needed to spend coinbase transactions
 };