[Bug] Fix contextCheckBlock for the first  block that it's a v1 block.
[Bug] Fix contextCheckBlock for the first  block that it's a v1 block.

Mrs-X/Darknet,Darknet-Crypto/Darknet,PIVX-Project/PIVX,Mrs-X/Darknet,Darknet-Crypto/Darknet,PIVX-Project/PIVX,PIVX-Project/PIVX,Mrs-X/PIVX,PIVX-Project/PIVX,Mrs-X/PIVX,Darknet-Crypto/Darknet,Mrs-X/Darknet,PIVX-Project/PIVX,Mrs-X/PIVX,Darknet-Crypto/Darknet,Darknet-Crypto/Darknet,PIVX-Project/PIVX,Mrs-X/Darknet,PIVX-Project/PIVX,Mrs-X/Darknet,PIVX-Project/PIVX,PIVX-Project/PIVX,Darknet-Crypto/Darknet,Mrs-X/PIVX,Mrs-X/PIVX,Mrs-X/PIVX,Mrs-X/Darknet