Determines whether the pane can float.
The framework calls this method to determine whether the pane can float.
During construction, you can set this ability by passing the AFX_CBRS_FLOAT flag to CBasePane::CreateEx.
The framework assumes that non-floating panes are static and that their docking state cannot change. Therefore, the framework does not save the docking state of non-floating panes.
The default implementation checks for the AFX_CBRS_FLOAT style.