fix(gridster): Add additiona error checking on widgets removal

…when remove_widget is called with an empty element we need to abandon the action early to avoid exceptions

Author: David Morse

dist/jquery.gridster.js

@@ -1,4 +1,4 @@
-/*! gridster.js - v0.6.10 - 2015-06-08
+/*! gridster.js - v0.6.10 - 2015-06-25
 * https://dsmorse.github.io/gridster.js/
 * Copyright (c) 2015 ducksboard; Licensed MIT */
 
@@ -1946,6 +1946,10 @@
 	 */
 	fn.remove_widget = function (el, silent, callback) {
 		var $el = el instanceof $ ? el : $(el);
+		if ($el.length === 0) {
+			//there is nothing to remove, so we can't remove it
+			return this;
+		}
 		var wgd = $el.coords().grid;
 		if (wgd === undefined) {
 			//there is no grid, so we can't remove it

dist/jquery.gridster.min.css

@@ -1,4 +1,4 @@
-/*! gridster.js - v0.6.10 - 2015-06-08
+/*! gridster.js - v0.6.10 - 2015-06-25
 * https://dsmorse.github.io/gridster.js/
 * Copyright (c) 2015 ducksboard; Licensed MIT */
 
@@ -1946,6 +1946,10 @@
 	 */
 	fn.remove_widget = function (el, silent, callback) {
 		var $el = el instanceof $ ? el : $(el);
+		if ($el.length === 0) {
+			//there is nothing to remove, so we can't remove it
+			return this;
+		}
 		var wgd = $el.coords().grid;
 		if (wgd === undefined) {
 			//there is no grid, so we can't remove it

dist/jquery.gridster.min.js

@@ -1048,6 +1048,10 @@
 	 */
 	fn.remove_widget = function (el, silent, callback) {
 		var $el = el instanceof $ ? el : $(el);
+		if ($el.length === 0) {
+			//there is nothing to remove, so we can't remove it
+			return this;
+		}
 		var wgd = $el.coords().grid;
 		if (wgd === undefined) {
 			//there is no grid, so we can't remove it