I work with ophthalmologists that specialize in the retina. They may or may not have someone check your visual acuity (how many letters can you read, etc.), but I would suspect not since you’d had that done recently. I’m afraid I don’t know about contacts - the patients I’ve dealt with haven’t worn any to their appointments, and I myself wear glasses. You should probably call the office and ask them, or ask at your appointment. (It’s sort of early here, no one’s around yet or I’d ask.)
Oh, and don’t hesitate to ask for a tissue after you have the drops put in, or after you get the light shined in your eyes. We occasionally forget to have one ready for patients. 
I should add that there are other tests that might be ordered, depending on what they see - though for floaters I’d suspect these won’t be necessary, so please don’t stress out about it. There’s an OCT (optical coherence tomography) which is basically looking into some eyepieces on a machine, some lights shine at you, takes about 10 minutes. Photographs can be taken of your retinas, or occasionally a fluorescein angiogram (you get an IV with some dye). There are also a couple tests of the visual field (how much peripheral vision you have, basically) - the more lengthy of the two involves staring into an eyepiece and pressing a button when you see a light. Again, for floaters, I’m not sure they’d want to run one of these, but I thought I’d mention them just in case.