Update rpc client header

(cherry picked from commit 091fa517c9)

store/store.go

@@ -196,6 +196,26 @@ func (bs *BlockStore) LoadBlockMeta(height int64) *types.BlockMeta {
 	return blockMeta
 }
 
+// LoadBlockMetaByHash returns the blockmeta who's header corresponds to the given
+// hash. If none is found, returns nil.
+func (bs *BlockStore) LoadBlockMetaByHash(hash []byte) *types.BlockMeta {
+	bz, err := bs.db.Get(calcBlockHashKey(hash))
+	if err != nil {
+		panic(err)
+	}
+	if len(bz) == 0 {
+		return nil
+	}
+
+	s := string(bz)
+	height, err := strconv.ParseInt(s, 10, 64)
+
+	if err != nil {
+		panic(fmt.Sprintf("failed to extract height from %s: %v", s, err))
+	}
+	return bs.LoadBlockMeta(height)
+}
+
 // LoadBlockCommit returns the Commit for the given height.
 // This commit consists of the +2/3 and other Precommit-votes for block at `height`,
 // and it comes from the block.LastCommit for `height+1`.