The new wallpaper picker will add several new functionalities that need metrics (the list may be expanded later):
1) 'My photos' section: see how many local files a user have under the
Downloads folder, so that we can decide if we want to fetch the
file names incrementally.
2) 'Preview wallpaper': see how many users prefer to preview the
wallpaper before actually setting it.
3) 'Learn more' links: see how many users are actually interested in
knowing more about the photographer/info of the wallpaper.
Comment 1 by wzang@chromium.org
, Feb 8 2018