fix(lib/babe): call AddBlock in BABE synchronously (ChainSafe#1585)

Author: noot

dot/core/service.go

@@ -284,12 +284,7 @@ func (s *Service) handleReceivedBlock(block *types.Block) (err error) {
 		return ErrNilBlockState
 	}
 
-	err = s.blockState.AddBlock(block)
-	if err != nil {
-		return err
-	}
-
-	logger.Debug("added block from BABE", "header", block.Header, "body", block.Body)
+	logger.Debug("got block from BABE", "header", block.Header, "body", block.Body)
 
 	msg := &network.BlockAnnounceMessage{
 		ParentHash:     block.Header.ParentHash,

lib/babe/babe.go

@@ -505,6 +505,11 @@ func (b *Service) handleSlot(slotNum uint64) error {
 	logger.Info("built block", "hash", hash.String(), "number", block.Header.Number, "slot", slotNum)
 	logger.Debug("built block", "header", block.Header, "body", block.Body, "parent", parent.Hash())
 
+	err = b.blockState.AddBlock(block)
+	if err != nil {
+		return err
+	}
+
 	err = b.safeSend(*block)
 	if err != nil {
 		logger.Error("failed to send block to core", "error", err)