Maker check DAO health when handling OfferAvailabilityRequest.

[ghost]

If some cases where the offer maker's DAO is out of sync, any OfferAvailabilityRequests result in a failed trade.

This PR adds a check of the DAO when handling OfferAvailabilityRequests, thus preventing unnecessary failed trades.

The maker will be shown a popup informing them to resync the DAO.

If their BTC chain is not synced, they will be shown an appropriate message.

Previously the maker was oblivious to being in a bad state.

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Background info:

It was seen in production that a maker's out of sync DAO was only detected after the offer availability handshake, during trade INIT. Ideally the offer availability stage should detect early and prevent the failed trade.

jan.-21 19:03:45.036 [JavaFX Application Thread] INFO  b.c.o.OpenOfferManager: Received OfferAvailabilityRequest from rinui343p5ytt2jy6qixlxowwnwkgz4ii4gocgpuuqo7ze76rw4vcnid.onion:9999 with offerId 5671366-cbf7b333-e6b1-4c60-81a3-8b578476dafa-198 and uid d87c482c-120e-4745-86a3-3a83175a7fbc 
jan.-21 19:03:46.030 [JavaFX Application Thread] INFO  b.c.offer.Offer: Price at take-offer time: id=5671366, currency=BRL, takersPrice=1390373665, makersPrice=1390373665, deviation=0.0% 
jan.-21 19:03:46.032 [JavaFX Application Thread] INFO  b.c.o.OpenOfferManager: Send OfferAvailabilityResponse with offerId 5671366-cbf7b333-e6b1-4c60-81a3-8b578476dafa-198 and uid 5e8f34cf-dfbf-41a2-a896-4a9a91d733cd to peer rinui343p5ytt2jy6qixlxowwnwkgz4ii4gocgpuuqo7ze76rw4vcnid.onion:9999 
jan.-21 19:03:46.033 [JavaFX Application Thread] INFO  b.c.o.OpenOfferManager: Send AckMessage for OfferAvailabilityRequest to peer rinui343p5ytt2jy6qixlxowwnwkgz4ii4gocgpuuqo7ze76rw4vcnid.onion:9999 with offerId 5671366-cbf7b333-e6b1-4c60-81a3-8b578476dafa-198 and sourceUid d87c482c-120e-4745-86a3-3a83175a7fbc 
jan.-21 19:03:46.035 [JavaFX Application Thread] INFO  b.c.o.OpenOfferManager: OfferAvailabilityResponse arrived at peer: offerId=5671366-cbf7b333-e6b1-4c60-81a3-8b578476dafa-198; uid=5e8f34cf-dfbf-41a2-a896-4a9a91d733cd 
jan.-21 19:03:46.087 [JavaFX Application Thread] INFO  b.c.o.OpenOfferManager: AckMessage for OfferAvailabilityRequest arrived at takersNodeAddress rinui343p5ytt2jy6qixlxowwnwkgz4ii4gocgpuuqo7ze76rw4vcnid.onion:9999. offerId=5671366-cbf7b333-e6b1-4c60-81a3-8b578476dafa-198, sourceUid=d87c482c-120e-4745-86a3-3a83175a7fbc 
jan.-21 19:03:47.440 [JavaFX Application Thread] INFO  b.c.o.OpenOfferManager: Received AckMessage for OfferAvailabilityResponse with offerId 5671366-cbf7b333-e6b1-4c60-81a3-8b578476dafa-198 and uid 5e8f34cf-dfbf-41a2-a896-4a9a91d733cd 
jan.-21 19:03:47.693 [JavaFX Application Thread] INFO  b.c.t.TradeManager: Received inputsForDepositTxRequest from rinui343p5ytt2jy6qixlxowwnwkgz4ii4gocgpuuqo7ze76rw4vcnid.onion:9999 with tradeId 5671366-cbf7b333-e6b1-4c60-81a3-8b578476dafa-198 and uid d3affe1b-5dcf-4e6d-8481-f14abd25d2b2 
jan.-21 19:03:47.694 [JavaFX Application Thread] INFO  b.c.n.a.TradeEvents: We got a new trade. id=5671366-cbf7b333-e6b1-4c60-81a3-8b578476dafa-198 
jan.-21 19:03:47.694 [JavaFX Application Thread] INFO  b.c.t.p.FluentProtocol$Condition: We received a InputsForDepositTxRequest at phase INIT and state PREPARATION, tradeId=5671366-cbf7b333-e6b1-4c60-81a3-8b578476dafa-198 
jan.-21 19:03:47.694 [JavaFX Application Thread] INFO  b.c.t.TaskRunner: Run task: CheckIfDaoStateIsInSync 
jan.-21 19:03:47.696 [JavaFX Application Thread] ERROR b.c.t.Task: An error occurred at task: CheckIfDaoStateIsInSync
Exception message: DAO state is not in sync with seed nodes 
jan.-21 19:03:47.696 [JavaFX Application Thread] ERROR b.c.t.TaskRunner: Task failed: CheckIfDaoStateIsInSync / errorMessage: An error occurred at task: CheckIfDaoStateIsInSync
Exception message: DAO state is not in sync with seed nodes 
jan.-21 19:03:47.697 [JavaFX Application Thread] ERROR b.c.t.p.TradeProtocol: Task runner failed with error An error occurred at task: CheckIfDaoStateIsInSync
Exception message: DAO state is not in sync with seed nodes. Triggered from InputsForDepositTxRequest 

[alejandrogarcia83]

utACK