Fix: eventcatcher widget - variables can be undefined (#6668)

* Fix: eventcatcher widget - variables can be undefined

* Fix: selectedNode can be an svg where offsetLeft ... are undefined

* Make check for offsetLeft short

* remove second collectDOMNodeVariables

core/modules/widgets/eventcatcher.js

@@ -52,7 +52,7 @@ EventWidget.prototype.render = function(parent,nextSibling) {
 				selectedNode = event.target,
 				selectedNodeRect,
 				catcherNodeRect,
-				variables;
+				variables = {};
 			// Firefox can fire dragover and dragenter events on text nodes instead of their parents
 			if(selectedNode.nodeType === 3) {
 				selectedNode = selectedNode.parentNode;