validation: Move FindForkInGlobalIndex to BlockManager

[META] This commit should be followed up by removing the comments and
       assertions meant only to show that the change is correct.

FindForkInGlobalIndex only acts on BlockManager.

Note to reviewers: Since FindForkInGlobalIndex is always called with
::ChainActive() as its first parameter, it is possible to move
FindForkInGlobalIndex to CChainState and remove this const CChain&
parameter to instead use m_chain. However, it seems like the original
intention was for FindForkInGlobalIndex to work with _any_ chain, not
just the current active chain. Let me know if this should be changed.

1 files changed, 3 insertions, 2 deletions

diff --git a/src/validation.cpp b/src/validation.cpp
index cabceca91b..69207fb529 100644
--- a/src/validation.cpp
+++ b/src/validation.cpp
@@ -175,14 +175,15 @@ CBlockIndex* BlockManager::LookupBlockIndex(const uint256& hash)
     return it == m_block_index.end() ? nullptr : it->second;
 }
 
-CBlockIndex* FindForkInGlobalIndex(const CChain& chain, const CBlockLocator& locator)
+CBlockIndex* BlockManager::FindForkInGlobalIndex(const CChain& chain, const CBlockLocator& locator)
 {
     AssertLockHeld(cs_main);
 
+    assert(std::addressof(g_chainman.m_blockman) == std::addressof(*this));
     // Find the latest block common to locator and chain - we expect that
     // locator.vHave is sorted descending by height.
     for (const uint256& hash : locator.vHave) {
-        CBlockIndex* pindex = g_chainman.m_blockman.LookupBlockIndex(hash);
+        CBlockIndex* pindex = LookupBlockIndex(hash);
         if (pindex) {
             if (chain.Contains(pindex))
                 return pindex;