Merge bitcoin#8515: A few mempool removal optimizations

0334430 Add some missing includes (Pieter Wuille)
4100499 Return shared_ptr<CTransaction> from mempool removes (Pieter Wuille)
51f2783 Make removed and conflicted arguments optional to remove (Pieter Wuille)
f48211b Bypass removeRecursive in removeForReorg (Pieter Wuille)

Author: laanwj

src/test/blockencodings_tests.cpp

@@ -80,8 +80,9 @@ BOOST_AUTO_TEST_CASE(SimpleRoundTripTest)
 
         BOOST_CHECK_EQUAL(pool.mapTx.find(block.vtx[2].GetHash())->GetSharedTx().use_count(), SHARED_TX_OFFSET + 1);
 
-        std::list<CTransaction> removed;
-        pool.removeRecursive(block.vtx[2], removed);
+
+        std::vector<std::shared_ptr<const CTransaction>> removed;
+        pool.removeRecursive(block.vtx[2], &removed);
         BOOST_CHECK_EQUAL(removed.size(), 1);
 
         CBlock block2;