Failed to fetch xids warning when closing any window

[Jeff Farthing]

Steps to reproduce:

1. Launch plank via terminal
2. Open a window, if needed, and then close a window

Output is the following:

[WARN 19:41:38.073745] Failed to fetch xids: GDBus.Error:org.freedesktop.DBus.Error.UnknownMethod: No such interface 'org.ayatana.bamf.application' on object at path /org/ayatana/bamf/application/959535951
[WARN 19:41:38.073899] [WindowControl:128] plank_services_windows_window_control_get_num_windows: runtime check failed: (_tmp2_ != NULL)

Plank version: 0.7.1.1142
Distro: Ubuntu 14.04.1
Window manager: Muffin
X version: 1:7.7+1ubuntu8
Video card: ATI Radeon 5450
Desktop environment: Cinnamon 2.4.5