Protects against a null atext in cloneAText

src/node/db/Pad.js

@@ -188,7 +188,12 @@ Pad.prototype.getInternalRevisionAText = function getInternalRevisionAText(targe
           db.getSub("pad:"+_this.id+":revs:"+keyRev, ["meta", "atext"], function(err, _atext)
           {
             if(ERR(err, callback)) return;
-            atext = Changeset.cloneAText(_atext);
+            try {
+              atext = Changeset.cloneAText(_atext);
+            } catch (e) {
+              return callback(e);
+            }
+
             callback();
           });
         },

src/static/js/Changeset.js

@@ -1628,10 +1628,12 @@ exports.applyToAText = function (cs, atext, pool) {
  * @param atext {AText} 
  */
 exports.cloneAText = function (atext) {
-  return {
-    text: atext.text,
-    attribs: atext.attribs
-  };
+  if (atext) {
+    return {
+      text: atext.text,
+      attribs: atext.attribs
+    }
+  } else exports.error("atext is null");
 };
 
 /**