saveError on message sending without connection on private chat

js/models/conversations.js

@@ -1211,12 +1211,20 @@
 
         // We're offline!
         if (!textsecure.messaging) {
-          const errors = this.contactCollection.map(contact => {
+          let errors;
+          if (this.contactCollection.length) {
+            errors = this.contactCollection.map(contact => {
               const error = new Error('Network is not available');
               error.name = 'SendMessageNetworkError';
               error.number = contact.id;
               return error;
             });
+          } else {
+            const error = new Error('Network is not available');
+            error.name = 'SendMessageNetworkError';
+            error.number = this.id;
+            errors = [error];
+          }
           await message.saveErrors(errors);
           return null;
         }