Taking cues from an aunt who brings a string of random guys to family holiday gatherings may not be wise. Yet, in the pleasantly diverting rom-com “Holidate” (streaming on Netflix), that’s exactly what Sloane (Emma Roberts) does, with a twist. After meeting prickly, she and handsome strange Jackson enter into a pact. They’d been standing in a returns line at a mall, one-upping each other about the miseries of being single during holidays. Just ahead of New Year’s Eve (surely among the more demanding of connection holidays), the two agree to be one another’s faux dates for the heavy-pressure night.