Put logs when setWallpaper is called

Currently, we do have a log (out of DEBUG flag) when a live wallpaper is
set, but not when a static wallpaper is set.

Knowing at least the which flag is helpful for debugging.

Flag: EXEMPT no logical change
Bug: 278261563
Test: presubmit
Change-Id: Ia78d99d5fd7039ef89cf2c4855c3ac001d208d46