Its difficult to say unless samsung provides a detailed description on exactly what materials are used. We know that the exterior is stainless steel, but the grade of stainless steel will determine if and by how much, it is resistant to oxidation by the chlorine, and at what concentrations.
You must also consider what makes the watch water resistant, its going to be rubber gaskets and O-rings. Those materials can also suffer oxidation, but again their resistance is dependent on the method of manufacture and the compound.
There are also coloured surfaces that may have some types of dyes or paints, or electroplating which can be affected by oxidation due to chlorine, or allow a material underneath to be affected if the top surface is damaged such as a small scratch or dent.
I've used many watches in chlorinated water for hundreds of hours of use, all were G-shocks, and all had stainless steel parts and used rubber in areas that need sealing, and I've had no visible damage on them, they all work perfectly and no water ingress or damage to the seals.
I did that at my own risk however, and it cant be said for certain for any other manufacturer unless they release the material specifications for each component or they just tell us themselves if its resistant.
Without a samsung themselves making it public knowledge, or them releasing the material data sheets, you can't know for sure. Only experimental data such as anecdotal from other users who have tried it, or by taking the risk yourself can give any insight.
