Dbus with Wallpaper plugin - Can't set Value with type 0 to option "bg_image" with type 7

[Haowei Wen]

There is a demo of the dbus plugin at http://wiki.compiz.org/Plugins/Dbus:
dbus-send --print-reply --type=method_call --dest=org.freedesktop.compiz /org/freedesktop/compiz/wallpaper/screen0/bg_image org.freedesktop.compiz.set array:string:"/path/to/new/image1","/path/to/new/image2","/path/to/new/image3"
It sets a new image list for the Wallpaper plugin on screen0.
But when I execute it, it doesn't work and I will get the following logs:
compiz (core) - Warn: Can't set Value with type 0 to option "bg_image" with type 7

The packages I have installed:
compiz 1:0.9.12.2+16.04.20160526-0ubuntu1
compiz-core 1:0.9.12.2+16.04.20160526-0ubuntu1
compiz-plugins:amd64 1:0.9.12.2+16.04.20160526-0ubuntu1
compiz-plugins-default:amd64 1:0.9.12.2+16.04.20160526-0ubuntu1
compiz-plugins-extra 1:0.9.12.2+16.04.20160526-0ubuntu1
compiz-plugins-main 1:0.9.12.2+16.04.20160526-0ubuntu1
compiz-plugins-main-default 1:0.9.12.2+16.04.20160526-0ubuntu1