The requirement that was formerly contained in the UK ANO can now be found in EASA Part FCL Regulation 1178/2011. The UK ANO Article 79 continues to include the regulation regarding helicopters.
(5) For the purposes of this article, a helicopter is in flight from the moment the helicopter first
moves under its own power for the purpose of taking off until the rotors are next stopped.
EASA Part FCL:
‘Flight time’:
for aeroplanes, touring motor gliders and powered-lift, it means the total time from the moment an aircraft first moves for the purpose of taking off until the moment it finally comes to rest at the end of the flight;
for helicopters, it means the total time from the moment a helicopter’s rotor blades start turning until the moment the helicopter finally comes to rest at the end of the flight, and the rotor blades are stopped;
Taxiing with the intention to fly and then parking again can't be logged. I've been through this with the CAA before.
Clearly if you don't fly, there is no flight time, but taxi time before and after flight does count.