I came across a Yellow-vented Bulbul (Pycnonotus goiavier analis) swallowing the flower of the cucumber (Cucumis sativus) in my garden. It happened so fast that I had no time to photograph it. Subsequently I saw a bulbul loitering around my plant. I stood as near as possible waiting for a chance to photograph it swallowing a flower but nothing happened.
Birds do swallow flowers for their nectar. An earlier report documents the Yellow-vented Bulbul as well as the Red-whiskered Bulbul (Pycnonotus jocosus) feeding on the flowers and flower buds of the starfruit tree (Averrhoa carambola) HERE.