Javascript class to use new wp.media uploader to upload or use an existing image to use it in the wordpress custom menu using this plugin idea https://github.com/blazersix/simple-image-widget

menu_images.js

jQuery(function($) {
  var $control;
	mediaControl = {
// Initializes a new media manager or returns an existing frame.
// @see wp.media.featuredImage.frame()
	frame: function() {
		if ( this._frame )
			return this._frame;

		this._frame = wp.media({
			title: 'Set image to menu element',
			library: {
				type: 'image'
			},
			button: {
				text: 'Set image'
			},
			multiple: false
		});
		this._frame.on( 'open', this.updateFrame ).state('library').on( 'select', this.select );
		return this._frame;
	},
	select: function() {

	// Do something when the "update" button is clicked after a selection is made.
			attachment = this.get('selection').first().toJSON();
			
			var item_id = $control.data('itemid');
			var img_obj = $control.data('targetimg');
			var img_id = $control.data('targetid');
      
      //this is defined in functions.php via wp_ajax action
			$.post(ajaxurl,{action:'set_thumbnail',id:attachment.id,item:item_id}, function(data){
				if (data == 1) {
					console.log('done');
				}
			});

			$('.'+img_obj).attr('src', attachment.sizes.thumbnail.url);
			$('.'+img_id).val(attachment.id);
	},
	updateFrame: function() {
	// Do something when the media frame is opened.
	},
	init: function() {
		$('#menu-to-edit').on('click', '.set-post-thumbnail', function(e) {
			e.preventDefault();
			mediaControl.frame().open();
      //use control to save click object
			$control = $(this);
		});
    //delete function
		$('#menu-to-edit').on('click','.remove-post-thumbnail', function( event ) {
			event.preventDefault();
			event.stopPropagation();
			var obj = $(this);
			var img_obj = obj.data('targetimg');
			var item_id = obj.data('itemid');
      //this is defined in functions.php via wp_ajax action
			$.post(ajaxurl,{action:'delete_thumbnail',item:item_id}, function(data){
					if (data == 1) {
						$('.'+img_obj).attr('src', '');
						$('#delete-link-'+item_id).hide();
					}
			});

		});
	}
};
jQuery(document).ready(function($){
  if ( window.wp ) {
    mediaControl.init();
  }
});