More detail to the question is needed. I think that if the question is about Romanticism in Rushdie's "Midnight's Children," there will have to be more clarification in terms of what is being sought. I would say that there is an overall concern in trying to ascribe one literary movement to an entire national body of literature. Aspects might be present, and this would be where the clarification point would be fairly helpful. I am not certain that there is much in way of Romanticism in the work, as Rushdie is fairly mindful of deconstructing previous narratives in the establishment of his own. I would say that Saleem does possess some elements of Romanticism in his belief in the sincerity of his convictions and in his desire to establish the Midnight's Children's conference to bring collectivity to the children of midnight.
If you want to know about Romanticism and its place in Indian English literary tradition, it is a curious and impure absence. While traces can always be found, since the Indian English tradition is post-romantic in its very foundation of postcoloniality and a kind of cultural hybridity. In the diasporic poets like Agha Shahid Ali, there are traces of the Romantic, but in general one finds the tone of the Indian English Literature a little too ironic, sarcastic and realistic for romanticism. In some of Jayanta Mahapatra's poetry there is a curious combination of Romanticism and Modernism.
However, if you are talking about the Indian Romantic tradition, at the level of Eros, it goes back to ancient times of Kamasutra. Then we have the plays of Kalidasa and the whole of the Padavali, the poems of the great Rabindranath Tagore as dominant achievements of Romanticism of the Indian tradition.