Fix crash on startup if tray icon is missing or invalid.
Fix crash on startup if tray icon is missing or invalid.

svn path=/trunk/KDE/kdepim/akregator/; revision=676091

lefou/kdepim-noakonadi,lefou/kdepim-noakonadi,lefou/kdepim-noakonadi,lefou/kdepim-noakonadi,lefou/kdepim-noakonadi,lefou/kdepim-noakonadi