GtkSearchBar: don't peek out
GtkSearchBar: don't peek out

When the searchbar is hidden, a 1-pixel-high piece of it is
still peeking out, because visible widgets are always allocated
at least 1x1. Work around this by setting child-visible to FALSE
in this situation.

https://bugzilla.gnome.org/show_bug.cgi?id=724096

ahodesuka/gtk,ahodesuka/gtk,ahodesuka/gtk,jadahl/gtk,davidgumberg/gtk,jigpu/gtk,Adamovskiy/gtk,chergert/gtk,Lyude/gtk-,chergert/gtk,Adamovskiy/gtk,jadahl/gtk,alexlarsson/gtk,davidgumberg/gtk,jigpu/gtk,grubersjoe/adwaita,alexlarsson/gtk,grubersjoe/adwaita,grubersjoe/adwaita,Adamovskiy/gtk,chergert/gtk,grubersjoe/adwaita,chergert/gtk,jadahl/gtk,Lyude/gtk-,ahodesuka/gtk,alexlarsson/gtk,jigpu/gtk,Lyude/gtk-,jigpu/gtk,Adamovskiy/gtk,Adamovskiy/gtk,Adamovskiy/gtk,jadahl/gtk,jigpu/gtk,alexlarsson/gtk,jigpu/gtk,alexlarsson/gtk,alexlarsson/gtk,grubersjoe/adwaita,chergert/gtk,grubersjoe/adwaita,chergert/gtk,davidgumberg/gtk,jigpu/gtk,jadahl/gtk,Lyude/gtk-,Lyude/gtk-,Adamovskiy/gtk,alexlarsson/gtk,grubersjoe/adwaita,jadahl/gtk,davidgumberg/gtk,Lyude/gtk-,grubersjoe/adwaita,davidgumberg/gtk,jigpu/gtk,ahodesuka/gtk,davidgumberg/gtk,jadahl/gtk,davidgumberg/gtk,ahodesuka/gtk,ahodesuka/gtk,Lyude/gtk-,Lyude/gtk-,chergert/gtk,chergert/gtk,Adamovskiy/gtk,jadahl/gtk,davidgumberg/gtk,ahodesuka/gtk,alexlarsson/gtk