To the best of my knowledge, I don't think there is any organization in India, either in the public sector or the private sector, that has included "Marriage Leave" as a separate and special type of leave with wages/salary to be granted to employees in its Leave Policy. I also believe that this is the case in the rest of the world, with the exception of a few countries such as China, Spain, Poland, and Malta.
The general practice in India, as far as I can observe, is that employees, on the occasion of their marriage, which is usually well-planned in advance, utilize their earned leave for about 10 to 15 days with the prior approval of their employers.