Trout chimes in on the topic at the 40 second mark.
With so many spots to fill next year, they need to pay for several arms. I assume one of Adell/Marsh will be on the club, possibly out of spring training, making J-Up less vital. If a trade could net a moderate cost mid-tier arm to improve the pitching staff then yes. However, I don't think there will be enough of a quality return that helps the Angels in the short term for that scenario to play out.
That being said, if they are in contention at the trade deadline, AND, they acquire some pitching help, keep him and see how the team battles for a spot. If not, no brainer, get whatever you can. I just don't think it will be very much; if anything, prospects that wont help the big club for several years.