History of HubBackend::block 2 changes

In crates/hub/src/protocol.rs, lines 107–109 on faf5246c900e9ff6804832bff4ab4fc8188bad6a7220901e6209658ac70261c8. Every change that wrote or deleted one of these lines, or deleted a line from between them. Exact, because each line keeps its identity across edits; edits elsewhere in the file are not here. Also: oxy log -L 107,109:crates/hub/src/protocol.rs.