History of Engine::tick 2 changes

In crates/backdrop/src/lib.rs, lines 107–134 on 046e3352cdfde9e656f0b864f482618b96e792c2c794cf756a2e85e9fc54e938. 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 107,134:crates/backdrop/src/lib.rs.