Add todos

Author: pawanjay176

beacon_node/beacon_chain/src/blob_verification.rs

@@ -105,6 +105,7 @@ impl<'a, T: BeaconChainTypes> VerifiedBlobsSidecar<'a, T> {
         chain: &BeaconChain<T>,
     ) -> Result<Self, BlobError> {
         let blob_slot = blob_sidecar.message.beacon_block_slot;
+        let blob_root = blob_sidecar.message.beacon_block_root;
         // Do not gossip or process blobs from future or past slots.
         let latest_permissible_slot = chain
             .slot_clock
@@ -117,6 +118,9 @@ impl<'a, T: BeaconChainTypes> VerifiedBlobsSidecar<'a, T> {
             });
         }
 
+        // TODO: return `UnknownHeadBlock` if blob_root doesn't exist in fork choice
+        // and wherever it could be found.
+
         let earliest_permissible_slot = chain
             .slot_clock
             .now_with_past_tolerance(MAXIMUM_GOSSIP_CLOCK_DISPARITY)