Chris Brown -- Rihanna Still Close to His Heart

Chris Brown may be necking with Rihanna again ... with his current girlfriend right by his side.

CB and Karrueche Tran were all over L.A. Tuesday promoting his new album. Chris has been wearing a necklace with an angel on it ... that looks exactly like Rihanna's.

Our photog asked Chris if the necklace was a gift from Rihanna ... but he was mum.

But sources close to Chris tell us the necklace has no connection to Rihanna. We're guessing Chris knew exactly what he was doing -- getting people to talk about him just as his album drops.

Smart.