On the 777 FMC there are two entries, Drag & FF: “-.-/-.-“
The aircraft will have a historical FF degradation, which would be checked before each flight. In the event of an MEL item (eg leave APU running during flight), you may have two corrections: one for increased fuel-flow, and the other for drag, as the APU door is open. The effect of the (fuel) penalty would be the same, but the Drag should also influence the overall profile.
I imagine in this case the effect would be negligible, unlike adding EAI use on the VNAV descent page.
A quick review if the MEL/CDL should identify these items with FF or Drag penalties.
Good luck.