WallpaperCropper: fix lockscreen wallpaper "Set wallpaper" string

The string is wrong and does not reflect the correct action the user is
about to apply.

Signed-off-by: Roman Birg <roman@cyngn.com>

Conflicts:
	packages/WallpaperCropper/res/values/cm_strings.xml

Change-Id: If90aa68217e061645267e1cb3fb7bbe3e5101e9a
Merge "WallpaperCropper: fix lockscreen wallpaper "Set wallpaper" string" into kitkat3