ValidationData: StorageDescriptor<[], {
    max_pov_size: number;
    parent_head: Binary;
    relay_parent_number: number;
    relay_parent_storage_root: FixedSizeBinary<32>;
}, true, never>

The [PersistedValidationData] set for this block. This value is expected to be set only once per block and it's never stored in the trie.