History of label 3 changes

In crates/oh/src/main.rs, lines 1172–1203 on image-check. 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 1172,1203:crates/oh/src/main.rs.