Merge branch 'fix-droplab-rendering' into 'master'

Fix droplab rendering template when data-dynamic selector is unavailable

Closes gitlab-ee#1655

See merge request !9012

app/assets/javascripts/droplab/droplab_ajax.js

@@ -78,8 +78,8 @@ require('../window')(function(w){
     },
 
     destroy: function() {
-      if (this.listTemplate) {
-        var dynamicList = this.hook.list.list.querySelector('[data-dynamic]');
+      var dynamicList = this.hook.list.list.querySelector('[data-dynamic]');
+      if (this.listTemplate && dynamicList) {
         dynamicList.outerHTML = this.listTemplate;
       }
     }