Rviz error skipping XML document
Every time I load Rviz, I see exactly four of these errors in my console:
[ERROR] [1430107225.314958023]: Skipping XML Document "/opt/ros/indigo/share/rviz_backdrop/plugin_description.xml" which had no Root Element. This likely means the XML is malformed or missing.
No file called /opt/ros/indigo/share/rviz_backdrop/plugin_description.xml seems to exist, even though I have all the ros-indigo-rviz-* packages installed.
Is this anything I should be concerned about? How do I fix it?