History of Engine::fit 3 changes

In crates/backdrop/src/lib.rs, lines 65–81 on d366306dae7d601bf141448c5454b89299847bb45ce14f84a23ffd13906a1c24. 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 65,81:crates/backdrop/src/lib.rs.