return null for .json resources if result is falcy
return null for .json resources if result is falcy

tyanas/basisjs,tyanas/basisjs,tyanas/basisjs,smelukov/basisjs,fateevv/basisjs,istrel/basisjs,basisjs/basisjs,fateevv/basisjs,istrel/basisjs,basisjs/basisjs,istrel/basisjs,smelukov/basisjs,basisjs/basisjs,smelukov/basisjs,fateevv/basisjs