I think it's related to P2Pool. It seems that when it founds a new bitcoin block, P2Pool adds a "marker" in the coinbase transaction (see last output from this
tx).
This output script (0x20 0x83e03b27ad09e5128d13a84c1154bba2a526f65f52a6d4e6759a8edfe4419568) says push 32 bytes (0x20) of data (0x83e03...) onto the stack when you must evaluate the script. This is a very strange output script but I guess it's related to how P2Pool works.
The
transaction you've spotted cleans the UTXO set by "spending" these dust outputs and my best guess is that the address "1HfA1KHC7bT1hnPPCjpj9CB4koLM4Hz8Va" is controlled by P2Pool.