Create components/wallpaper directory

Move wallpaper_resizer* from "ash/desktop_background" to "extensions/components/wallpaper"

Move enum WallpaperLayout to a separate file extensions/components/wallpaper/wallpaper_layout_enum.h
that can be accessible from "extensions/components/wallpaper" and "ash/desktop_background"

BUG=431389

Review URL: https://codereview.chromium.org/720473002

Cr-Commit-Position: refs/heads/master@{#307367}
35 files changed