message: [net processing] Clarify UpdatedBlockTip()
diff: @@ -1296,8 +1296,9 @@ void PeerManager::UpdatedBlockTip(const CBlockIndex *pindexNew, const CBlockInde
  m_connman.SetBestHeight(pindexNew->nHeight);
  SetServiceFlagsIBDCache(!fInitialDownload);
  - // Relay inventory, but don't relay old inventory during initial block download.
  - if (!fInitialDownload) {
  + // Don't relay inventory during initial block download.
  + if (fInitialDownload) return;
  +
  // Find the hashes of all blocks that weren't previously in the best chain.
  std::vector<uint256> vHashes;
  const CBlockIndex *pindexToAnnounce = pindexNew;
  @@ -1310,6 +1311,8 @@ void PeerManager::UpdatedBlockTip(const CBlockIndex *pindexNew, const CBlockInde
  break;
  }
  }
  +
  + // Relay to all peers
  m_connman.ForEachNode([&vHashes](CNode* pnode) {
  LOCK(pnode->cs_inventory);
  for (const uint256& hash : reverse_iterate(vHashes)) {
  @@ -1318,7 +1321,6 @@ void PeerManager::UpdatedBlockTip(const CBlockIndex *pindexNew, const CBlockInde
  });
  m_connman.WakeMessageHandler();
  }
  -}
  /**
  * Handle invalid block rejection and consequent peer discouragement, maintain which
  