It would appear that the official felt that Chen Long took the shuttle on LCW's side of the net. The replay shows that the initial contact was on CL's own side. But, WOW, can you blame the official's eye for not being able to pick up such an amazingly tight shot?
Ah that's what I thought but the commentator seemed to agree with the call even after seeing the slow motion replay so I thought I'm missing something here.