Short after conditioner. Reasoning: Noise pickup.
A good conditioner removes audible noise and EMI/RFI as well from the AC signal. However this output is not guaranteed to stay clean. To ensure the signal stays clean you want a short and shielded power cord after the conditioner. The longer that cord the higher the chances of noise pickup.
Same reason why I recommend not putting in noise polluting devices after the conditioner. This means PC's, network power supplies, etc.