Prevent delete record if screen is not deletable

Closes #13885
(grafted from 55434555b4c8e408cec6b08e53306335c17206ee)

--HG--
branch : 6.0

sao/src/tab.js

@@ -901,7 +901,8 @@
             }.bind(this));
         },
         delete_: function() {
-            if (!Sao.common.MODELACCESS.get(this.screen.model_name)['delete']) {
+            if (!Sao.common.MODELACCESS.get(this.screen.model_name)['delete']
+                || !this.screen.deletable) {
                 return jQuery.when();
             }
             var msg;