epaint: Memoize individual lines during text layout #13969

Job	Run time
Format + check + test	2m 57s
android	37s
cargo-deny aarch64-apple-darwin	37s
Check wasm32 + wasm-bindgen	2m 32s
cargo-deny aarch64-linux-android	40s
Check wasm32+atomics	1m 36s
ios	1m 32s
cargo-deny i686-pc-windows-gnu	37s
Run tests	1m 42s
cargo-deny i686-pc-windows-msvc	36s
Check Windows	2m 37s
cargo-deny i686-unknown-linux-gnu	40s
cargo-deny wasm32-unknown-unknown	38s
cargo-deny x86_64-apple-darwin	39s
cargo-deny x86_64-pc-windows-gnu	37s
cargo-deny x86_64-pc-windows-msvc	39s
cargo-deny x86_64-unknown-linux-gnu	39s
cargo-deny x86_64-unknown-linux-musl	40s
cargo-deny x86_64-unknown-redox	37s
	21m 12s

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