Rust

Improve error message in ColorImage::region #13642

Job	Run time
Check wasm32+atomics	1m 33s
Format + check + test	3m 15s
android	22s
cargo-deny aarch64-apple-darwin	37s
Check wasm32 + wasm-bindgen	2m 54s
ios	24s
cargo-deny aarch64-linux-android	40s
cargo-deny i686-pc-windows-gnu	40s
cargo-deny i686-pc-windows-msvc	43s
Run tests	1m 37s
Check Windows	1m 30s
cargo-deny i686-unknown-linux-gnu	40s
cargo-deny wasm32-unknown-unknown	38s
cargo-deny x86_64-apple-darwin	41s
cargo-deny x86_64-pc-windows-gnu	50s
cargo-deny x86_64-pc-windows-msvc	39s
cargo-deny x86_64-unknown-linux-gnu	40s
cargo-deny x86_64-unknown-linux-musl	51s
cargo-deny x86_64-unknown-redox	37s
	19m 51s

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