fix exception when SourceWrapper content is non-object
fix exception when SourceWrapper content is non-object

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