src/vs/editor/common/core/textChange.ts/TextChangeCompressor/_rebaseCurr
class TextChangeCompressor:	private static _rebaseCurr(prevDeltaOffset: number, currEdit: TextChange): TextChange {
		return new TextChange(
			currEdit.oldPosition - prevDeltaOffset,
			currEdit.oldText,
			currEdit.newPosition,
			currEdit.newText
		);
	}