History of propagate 2 changes

In crates/hub/src/diffusion.rs, lines 1067–1069 on v0.9.23. 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 1067,1069:crates/hub/src/diffusion.rs.