Fix blocked panning bug
Fix blocked panning bug

The detection of anchor update was done incorrectly in the case when
panning down (i.e. going to the north)

Signed-off-by: Jiří Techet <af18a4329e30c3b95edc4d3e647176d16d87c9c7@gmail.com>

StanciuMarius/Libchamplain-map-wrapping,StanciuMarius/Libchamplain-map-wrapping,StanciuMarius/Libchamplain-map-wrapping,potyl/champlain,potyl/champlain,Distrotech/libchamplain,GNOME/perl-Champlain,PabloCastellano/libchamplain,GNOME/perl-Gtk2-Champlain,GNOME/libchamplain,PabloCastellano/libchamplain,PabloCastellano/libchamplain,Distrotech/libchamplain,GNOME/perl-Champlain,StanciuMarius/Libchamplain-map-wrapping,Distrotech/libchamplain,potyl/champlain,potyl/champlain,GNOME/libchamplain,Distrotech/libchamplain,GNOME/perl-Gtk2-Champlain,PabloCastellano/libchamplain,PabloCastellano/libchamplain,StanciuMarius/Libchamplain-map-wrapping,Distrotech/libchamplain