map: store zoom/center instead of bounds

lib/map.js

@@ -122,7 +122,7 @@ define(["map/clientlayer", "map/labelslayer",
       var self = this
       var barycenter
       var groupOnline, groupOffline, groupNew, groupLost, groupLines
-      var savedBounds
+      var savedView
 
       var map, userLocation
       var layerControl
@@ -136,7 +136,8 @@ define(["map/clientlayer", "map/labelslayer",
       })
 
       function saveView() {
-        savedBounds = map.getBounds()
+        savedView = {center: map.getCenter(),
+                     zoom: map.getZoom()}
       }
 
       function enableTracking() {
@@ -286,8 +287,8 @@ define(["map/clientlayer", "map/labelslayer",
         if (!nopanzoom)
           if (m)
             goto(m)
-          else if (savedBounds)
-            map.fitBounds(savedBounds)
+          else if (savedView)
+            map.setView(savedView.center, savedView.zoom)
           else
             resetZoom()
       }