Taylor Swift has fulfilled one of her 'wildest dreams' by performing with legendary rockers, The Rolling Stones. Harry Styles' ex-girlfriend took to the stage with Mick Jagger and Co in Chicago last night (June 3), where they sung As Tears Go By together.After their stint on stage, the 23-year old country songbird took to Twitter to post a black and white snap of herself with Jagger, accompanied with the caption: "Filing this under 'friends forever'. ‪@MickJagger‬."MTV She then uploaded another photo, this time of herself holding hands with Jagger on stage, with Swift commenting: "Filing this under 'never in my wildest dreams'.Thank you ‪@RollingStones‬ for inviting me to Chicago to sing with you.