Restore the form to change the background image

drag_and_drop_v2/public/css/drag_and_drop_edit.css

@@ -206,6 +206,10 @@
     margin-left: 0;
 }
 
+.xblock--drag-and-drop .drag-builder .target-image-form input {
+    width: 50%;
+}
+
 .xblock--drag-and-drop .zones-form .zone-row label {
     display: inline-block;
     width: 18%;

drag_and_drop_v2/public/js/drag_and_drop_edit.js

@@ -162,6 +162,7 @@ function DragAndDropEditBlock(runtime, element) {
                             e.preventDefault();
 
                             _fn.data.targetImg = $('.target-image-form input', element).val();
+                            _fn.$target.css('background', 'url(' + _fn.data.targetImg + ') no-repeat');
 
                             // Placeholder shim for IE9
                             $.placeholder.shim();

drag_and_drop_v2/templates/html/drag_and_drop_edit.html

@@ -26,6 +26,11 @@
                 <h3>Zone Positions</h3>
             </header>
             <section class="tab-content">
+                <section class="tab-content target-image-form">
+                    <label>New background URL:</label>
+                    <input type="text">
+                    <button class="btn">Change background</button>
+                </section>
                 <div class="items">
                     <form class="zones-form"></form>
                     <a href="#" class="add-zone add-element"><div class="icon add"></div>Add a zone</a>