go/consensus/tendermint: Fix BlockHeight in InitChain

Previously when ctx.BlockHeight() was called from InitChain it always returned
the zero height which was incorrect. Make sure to return one height less than
the initial height in this case.

go/consensus/tendermint/abci/state.go

@@ -79,9 +79,12 @@ func (s *applicationState) NewContext(mode api.ContextMode, now time.Time) *api.
 
 	var blockCtx *api.BlockContext
 	var state mkvs.Tree
+	blockHeight := int64(s.stateRoot.Version)
 	switch mode {
 	case api.ContextInitChain:
 		state = s.deliverTxTree
+		// Configure block height so that current height will be correctly computed.
+		blockHeight = int64(s.initialHeight) - 1
 	case api.ContextCheckTx:
 		state = s.checkTxTree
 	case api.ContextDeliverTx, api.ContextBeginBlock, api.ContextEndBlock:
@@ -103,7 +106,7 @@ func (s *applicationState) NewContext(mode api.ContextMode, now time.Time) *api.
 		api.NewNopGasAccountant(),
 		s,
 		state,
-		int64(s.stateRoot.Version),
+		blockHeight,
 		blockCtx,
 		int64(s.initialHeight),
 	)