From a93e0b85df8b04f54c13eccc76fe26671649770c Mon Sep 17 00:00:00 2001
From: Tom Payne <twpayne@gmail.com>
Date: Fri, 13 Dec 2013 16:16:59 +0100
Subject: [PATCH] Improve type checking in ol.interaction.DragPan

---
 src/ol/interaction/dragpaninteraction.js | 1 +
 1 file changed, 1 insertion(+)

diff --git a/src/ol/interaction/dragpaninteraction.js b/src/ol/interaction/dragpaninteraction.js
index 8ecb343efa..2b2b3231d4 100644
--- a/src/ol/interaction/dragpaninteraction.js
+++ b/src/ol/interaction/dragpaninteraction.js
@@ -89,6 +89,7 @@ ol.interaction.DragPan.prototype.handleDragEnd = function(mapBrowserEvent) {
 
   if (this.kinetic_ && this.kinetic_.end()) {
     var view2D = view.getView2D();
+    goog.asserts.assertInstanceof(view2D, ol.View2D);
     var view2DState = view2D.getView2DState();
     var distance = this.kinetic_.getDistance();
     var angle = this.kinetic_.getAngle();