Synchronize Monaco Editor-based custom editor undo stack with VS Code

[lppedd]

We are using the standalone package of Monaco Editor for some of our custom editor webviews. The major problem I see is being able to emit the correct CustomDocumentEditEvent so that the undo and redo source of truth is VS Code, and not Monaco Editor.

Is there an existing strategy for this specific use case?

Currently, what I may try out is having my own stack strategy:

1. Listen for onDidChangeModelContent events
2. On whitespace, newline, or timeout, push a new stack entry with editorModel.pushStackElement() and find out how many entries are present in the stack by checking undoRedoService._editStacks.get(key)._past
3. Send out a CustomDocumentEditEvent with the entry count for undoRedoService._editStacks.get(key)._past
4. When an Undo operation is requested from VS Code, programmatically call undo n-times based on the entry count.

The same should probably apply for redos.