It's too early to say about whitewash, it's just second T20. Let India wins this first then we can talk about whitewash. Sri Lanka recently avoided whitewash against Australia by wining the last T20 and ending series 4-1. In this series SL are capable of winning just one or two match not the series.
With the current form of Indian and Sri Lankan teams in this t20 format we can expect a whitewash in this series because today India is looking for their 11th straight win and Sri Lanka is not good enough to have any chance for fighting back with very poor in both batting and bowling after very badly defeat against Australia.
Even they won last match of this lost series but still they are completely down-and-out by classic team and now facing World's No 1 team in this format which is worst for their current form and squad who is most depending on new players which need some more time and experience for giving better results.
A good thing for Sri Lanka now they can't drop from their current position in twenty ranking as they are staying at 10th.