Soundgarden frontman Chris Cornell has a rather sappy original song called “The Promise,” a cut from the soundtrack of the Christian Bale- and Oscar Isaac-starring historical drama of the same name. The Promise comes to wide release tomorrow (alas, with a 45% Rotten Tomatoes rating) and last night, Cornell brought a strong performance of the song to The Tonight Show Starring Jimmy Fallon. Soundgarden/Pearl Jam drummer…
