[Crash Report] Undo system crashes when redoing a shape's deletion

[Keavon]

Steps To Reproduce
Describe precisely how the crash occurred, step by step, starting with a new editor window.

1. Open the Graphite Editor at https://editor.graphite.design
2. Draw a shape such as an ellipse
3. Hit Delete
4. Undo (CtrlZ)
5. Redo(CtrlShiftZ), this causes the crash

Browser and OS
Chrome 96, Windows 10 or 11

Stack Trace
Copied from the crash dialog in the Graphite Editor:

panicked at 'called `Result::unwrap()` on an `Err` value: LayerNotFound', editor/src/document/document_file.rs:382:84

Error
    at https://editor.graphite.design/js/app.5d3a541f.js:1:14025
    at a (https://editor.graphite.design/js/app.5d3a541f.js:1:162234)
    at https://editor.graphite.design/js/chunk-7dc2b365.e94737f5.js:1:7234
    at O (https://editor.graphite.design/js/chunk-7dc2b365.e94737f5.js:1:4444)
    at Object.Nn (https://editor.graphite.design/js/chunk-7dc2b365.e94737f5.js:1:7197)
    at __wbg_handleJsMessage_1da694b6d316550a (https://editor.graphite.design/js/app.5d3a541f.js:1:1123)
    at https://editor.graphite.design/a173269e1afc432cfd93.module.wasm:wasm-function[167]:0x6d6fd
    at https://editor.graphite.design/a173269e1afc432cfd93.module.wasm:wasm-function[472]:0x93736
    at https://editor.graphite.design/a173269e1afc432cfd93.module.wasm:wasm-function[1088]:0xa347e
    at https://editor.graphite.design/a173269e1afc432cfd93.module.wasm:wasm-function[564]:0x99479
    at https://editor.graphite.design/a173269e1afc432cfd93.module.wasm:wasm-function[672]:0x9e082
    at https://editor.graphite.design/a173269e1afc432cfd93.module.wasm:wasm-function[836]:0xa1be1
    at https://editor.graphite.design/a173269e1afc432cfd93.module.wasm:wasm-function[860]:0xa20be
    at https://editor.graphite.design/a173269e1afc432cfd93.module.wasm:wasm-function[683]:0x9e610
    at https://editor.graphite.design/a173269e1afc432cfd93.module.wasm:wasm-function[154]:0x6a9f6
    at https://editor.graphite.design/a173269e1afc432cfd93.module.wasm:wasm-function[164]:0x6cd46
    at https://editor.graphite.design/a173269e1afc432cfd93.module.wasm:wasm-function[14]:0x141e5
    at https://editor.graphite.design/a173269e1afc432cfd93.module.wasm:wasm-function[21]:0x28934
    at https://editor.graphite.design/a173269e1afc432cfd93.module.wasm:wasm-function[137]:0x665b3
    at https://editor.graphite.design/a173269e1afc432cfd93.module.wasm:wasm-function[267]:0x7f139
    at https://editor.graphite.design/a173269e1afc432cfd93.module.wasm:wasm-function[505]:0x95cd8
    at https://editor.graphite.design/a173269e1afc432cfd93.module.wasm:wasm-function[849]:0xa1e88
    at Proxy.Y (https://editor.graphite.design/js/chunk-7dc2b365.e94737f5.js:1:5615)
    at Proxy.<anonymous> (https://editor.graphite.design/js/app.5d3a541f.js:1:7158)
    at F (https://editor.graphite.design/js/app.5d3a541f.js:1:10006)