Always report the real wallpaper visibility when wallpaper supports

ambient mode.

On wear os, wallpaper needs to be visible during STATE_DOZE and
STATE_DOZE_SUSPEND. This changes the wallpaper visibility reporting
logic so that wallpaper can be visible as long as it supports ambient
mode.

Since all wear os wallpapers (watch faces) are supposed to be visible
during ambient mode, this change also makes all wear os wallpapers
support ambient mode by default, and exclude watches from the ambient
wallpaper permission check.

Bug: 287174294
Test: wallpaper is now visible during ambient mode
Change-Id: Ic4fa68d8040782e659aac100b10a8126a232baa1