am 394ef56d: am aecf2c65: am 76c9d31c: Revert "adding set wallpaper sample code in ApiDemos."

Merge commit '394ef56df8af1e569458f6159ce79b055bb846ef'

* commit '394ef56df8af1e569458f6159ce79b055bb846ef':
  Revert "adding set wallpaper sample code in ApiDemos."