fixed gc circular ref issue
fixed gc circular ref issue

Honoo/HubTurbo,saav/HubTurbo,HyungJon/HubTurbo,HyungJon/HubTurbo,Honoo/HubTurbo,ianngiaw/HubTurbo,ianngiaw/HubTurbo,saav/HubTurbo,gaieepo/HubTurbo,Sumei1009/HubTurbo,gaieepo/HubTurbo,Sumei1009/HubTurbo