History of propagate 2 changes

In crates/hub/src/diffusion.rs, lines 851–853 on 9aee52d392a67323824e269c3f0ffdf4c0e066e2bba44bd4d9204368f3a034a1. 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 851,853:crates/hub/src/diffusion.rs.