ros::init is called pretty early in rviz, before this could get called.  I can confirm that I do see this error message being printed.

Side note:  In rviz/src/rviz/visualizer_app.cpp in VisualizerApp::init() ROS_INFO() is used before ros::init() is called and I see that in the terminal.  Maybe that won't show up in the log?  (That function has nothing to do with this change).