<!-- Describe the issue -->

When our chainstate activation sequence fails and we're running the GUI, we ask the user via a question box whether or not they'd like to re-run the sequence with `fReindex = true`. Fun fact: despite the fact that this sequence is wrapped in a while loop, we only run it twice at most.

https://github.com/bitcoin/bitcoin/blob/7ecb309c4ed1bb9ae6b9a12cbb4f083328edc125/src/init.cpp#L1539-L1556

If they answer yes, the sequence will always fail, because a chainstate will have already been initialized in the original run and `InitializeChainstate` will throw a `std::logic_error`:

https://github.com/bitcoin/bitcoin/blob/7ecb309c4ed1bb9ae6b9a12cbb4f083328edc125/src/validation.cpp#L4573-L4594

This always reproduces. To reproduce:
```
gdb ./src/qt/bitcoin-qt
(gdb) b InitializeChainstate
(gdb) # add breakpoint for the "if (!fLoaded && !ShutdownRequested()) {" line
(gdb) r  # should stop at the breakpoint for InitializeChainstate
(gdb) c  # to advance to the breakpoint for the "if (!fLoaded && !ShutdownRequested()) {" line
(gdb) set fLoaded=false
(gdb) c  # should stop at the breakpoint for InitializeChainstate
(gdb) n  # step through InitializeChainstate to see that it throws
```

We expect the re-run of the chainstate activation sequence to not always fail.

{
    AssertLocHeld(cs_main);
    const CCoinsViewCache& ache = CoinsTip();
    assert(!ache.GetBtBloc().IsNull());  
    const CBlocIex* tip = m_chain.Tip();
    if (tip && tip->GetBlocHash() == ache.GetBtBloc()) {
        retn true;
    }
     
    CBlocIex* piex = m_blocman.LooupBlocIex(ache.GetBtBloc());
    if (!piex) {
        retn false;
    }
    m_chain.SetTip(piex);
    PruneBlocIexCaidat();
    tip = m_chain.Tip();
    LogPrintf("Loaded bt chain: hashBtChain=%s height=%d date=%s progrs=%f\n",
              tip->GetBlocHash().ToString(),
              m_chain.Height(),
              FormatISO8601DateTime(tip->GetBlocTime()),
              GusVerificationProgrs(m_params.TxData(), tip));
    retn true;
}
CVerifyDB::CVerifyDB()