Rust

Remove unsafe impl of Send and Sync for Painter #54

Job	Run time
Check wasm32 + wasm-bindgen	4m 52s
Format + check + test	9m 24s
android	35s
cargo-deny aarch64-apple-darwin	41s
Check Windows	2m 23s
cargo-deny aarch64-linux-android	59s
cargo-deny i686-pc-windows-gnu	1m 0s
cargo-deny i686-pc-windows-msvc	43s
cargo-deny i686-unknown-linux-gnu	42s
cargo-deny wasm32-unknown-unknown	41s
cargo-deny x86_64-apple-darwin	51s
cargo-deny x86_64-pc-windows-gnu	2m 40s
cargo-deny x86_64-pc-windows-msvc	39s
cargo-deny x86_64-unknown-linux-gnu	42s
cargo-deny x86_64-unknown-linux-musl	40s
cargo-deny x86_64-unknown-redox	54s
	28m 26s

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