export as imgae uses min not max function

CHANGELOG

@@ -2,6 +2,7 @@ minerva (13.1.3) stable; urgency=medium
   * Bug fix: refreshing list of projects or list of users doesn't change active
     page (#870)
   * Bug fix: submap list must be selected to export from every submap (#874)
+  * Bug fix: export map as image properly uses bottom limit (#875)
 
  -- Piotr Gawron <piotr.gawron@uni.lu> Wed,  14 Aug 2019 17:00:00 +0200
 

frontend-js/src/main/js/map/AbstractCustomMap.js

@@ -187,7 +187,7 @@ AbstractCustomMap.prototype.registerMapClickEvents = function () {
     var y1 = Math.max(0, topLeft.y);
 
     var x2 = Math.min(self.getModel().getWidth(), rightBottom.x);
-    var y2 = Math.max(self.getModel().getHeight(), rightBottom.y);
+    var y2 = Math.min(self.getModel().getHeight(), rightBottom.y);
 
     var polygon = "";
     polygon += x1 + "," + y1 + ";";