src/vs/editor/common/core/textChange.ts/TextChangeCompressor/_rebasePrev
class TextChangeCompressor:	private static _rebasePrev(currDeltaOffset: number, prevEdit: TextChange): TextChange {
		return new TextChange(
			prevEdit.oldPosition,
			prevEdit.oldText,
			prevEdit.newPosition + currDeltaOffset,
			prevEdit.newText
		);
	}