Register callbacks with `Context::on_begin_frame` and `on_end_frame`. #8889

Job	Run time
android	23s
cargo-deny aarch64-apple-darwin	46s
cargo-deny aarch64-linux-android	41s
Check wasm32 + wasm-bindgen	2m 30s
cargo-deny i686-pc-windows-gnu	41s
cargo-deny i686-pc-windows-msvc	44s
cargo-deny i686-unknown-linux-gnu	48s
cargo-deny wasm32-unknown-unknown	41s
Format + check + test	5m 50s
cargo-deny x86_64-apple-darwin	41s
cargo-deny x86_64-pc-windows-gnu	44s
cargo-deny x86_64-pc-windows-msvc	45s
cargo-deny x86_64-unknown-linux-gnu	37s
cargo-deny x86_64-unknown-linux-musl	56s
cargo-deny x86_64-unknown-redox	44s
Check Windows	1m 58s
	19m 29s

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