Remove use of goog.partial

Use Function.prototype.bind instead, see:
https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/Function/bind#Partially_applied_functions_(currying)

src/ol/interaction/draganddropinteraction.js

@@ -72,7 +72,7 @@ ol.interaction.DragAndDrop.handleDrop_ = function(event) {
     file = files.item(i);
     var reader = new FileReader();
     reader.addEventListener(ol.events.EventType.LOAD,
-        goog.partial(this.handleResult_, file).bind(this));
+        this.handleResult_.bind(this, file));
     reader.readAsText(file);
   }
 };