src/vs/editor/common/viewLayout/linesLayout.ts/LinesLayout/_insertWhitespace
class LinesLayout:	private _insertWhitespace(whitespace: EditorWhitespace): void {
		const insertIndex = LinesLayout.findInsertionIndex(this._arr, whitespace.afterLineNumber, whitespace.ordinal);
		this._arr.splice(insertIndex, 0, whitespace);
		this._prefixSumValidIndex = Math.min(this._prefixSumValidIndex, insertIndex - 1);
	}