New Topic is shown in Log In dialog

Precondition:

• create user with Create_post permission for specific branch(use this branch in the steps below

STR:

1. Go to JCommune, you should be logged out
2. Log in, go to branch and press New Topic
3. Open another tab in browser and log out there.
4. Return to previous tab and press the button to actually create a Topic.
   It will redirect you to the log in page which is correct.
5. Instead of using the shown form to log in, use the dialog by pressing Sign In in the right top corner. After actually loging in you'll see a surprise.

AR: you can see it in attachments.
ER: user should be logged in as usually directed to the page of created topic (if it was actually created) or to the page of errors if the post didn't pass validation.