BIP141: Commitment structure and deployment

Includes a fix by Suhas Daftuar and LongShao007

src/consensus/merkle.cpp

@@ -165,6 +165,17 @@ uint256 BlockMerkleRoot(const CBlock& block, bool* mutated)
     return ComputeMerkleRoot(leaves, mutated);
 }
 
+uint256 BlockWitnessMerkleRoot(const CBlock& block, bool* mutated)
+{
+    std::vector<uint256> leaves;
+    leaves.resize(block.vtx.size());
+    leaves[0].SetNull(); // The witness hash of the coinbase is 0.
+    for (size_t s = 1; s < block.vtx.size(); s++) {
+        leaves[s] = block.vtx[s].GetWitnessHash();
+    }
+    return ComputeMerkleRoot(leaves, mutated);
+}
+
 std::vector<uint256> BlockMerkleBranch(const CBlock& block, uint32_t position)
 {
     std::vector<uint256> leaves;