src/vs/workbench/api/common/extHostTypes.ts/Range/contains
class Range:	contains(positionOrRange: Position | Range): boolean {
		if (positionOrRange instanceof Range) {
			return this.contains(positionOrRange._start)
				&& this.contains(positionOrRange._end);

		} else if (positionOrRange instanceof Position) {
			if (positionOrRange.isBefore(this._start)) {
				return false;
			}
			if (this._end.isBefore(positionOrRange)) {
				return false;
			}
			return true;
		}
		return false;
	}