Hidden code in Instagram's Android app revealed a big new music feature (FB)

Instagram may be adding a feature that lets users add music in the background of their Stories.
Facebook has recently made licensing agreements with the major records, making a music service possible.
Your Instagram Stories could soon have a soundtrack featuring your favorite songs. 
Instagram is prepping a new feature, called Music Stickers, that will allow users to search for a particular song and add a "music overlay sticker" — or a clip of a song in the background of their St