What function does the Inductor and Resistor serve?
L1 reduces the noise generated by the converter. If too much electrical noise gets into the mains cord the product will fail EMC. 

L1 is far too small to reduce mains frequency artifacts. If L1 had enough inductance to attenuate mains frequency harmonic noise, the small cheap SMPS could double in size. Passive mains harmonic filtering is not cheap and when done properly, it involves a network of inductors and capacitors. 

Your resistor damps unwanted resonances in L1. It may have been added when a peak occured in a conducted EMC plot .