History of kernel 2 changes

In crates/flow/src/facts.rs, lines 41–49 on 3029d39be7723d077cc14a1327d212473e7115925a758759b5c13ffd424107e9. 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 41,49:crates/flow/src/facts.rs.