src/vs/workbench/contrib/notebook/browser/contrib/find/findModel.ts/FindModel/_matchesCountBeforeIndex
class FindModel:	private _matchesCountBeforeIndex(findMatches: CellFindMatchWithIndex[], index: number) {
		let prevMatchesCount = 0;
		for (let i = 0; i < index; i++) {
			prevMatchesCount += findMatches[i].matches.length;
		}

		return prevMatchesCount;
	}