Instead of calling it in response to any of the properties it depends on.
This also saves some calls to this function on startup (80 instead of 90 for me with 14 tray icons) and keeps plasmoids from shifting around just because their status changed from e.g. Active to AcceptingInput (like touchpad when it asks for whether you really want to disable touchpad with no mouse attached) although the item's effective visibility didn't actually change.

BUG: 375112
CCBUG: 365630
FIXED-IN: 5.10.0

• Disabling categories still completely hides items
• Active/passive change still moves items from compact rep to popup and vice-versa
• when touchpad applet asks for confirmation it no longer shifts around (used to move to the left-most (after notifications) position)

(I noticed that we don't actually support the HiddenStatus for plasmoids anymore which was originally introduced for system tray for applets to completely hide themselves)