This is a possible fix for #384.
To be honest I don't fully understand why this bug is happening, but I
have narrowed it down to the view stack in wlc and how sway orders views
in very specific situations (those described in #384).
Anyway this should fix the problem by eliminating the call to
`wlc_view_bring_to_front` which isn't really needed anyway since sending
all invisible views to the back is the same as bringing all visible
views to the front (rotating the view stack).
fa0526f3df