Spaces before email in "Sign up" dialog are not cut when one of the fields is incorrect or empty

Steps to reproduce:

1. Open sign up dialog
2. Fill in the form with correct data except captcha field and email field: before email value (input existing email) make some spaces
3. Click on Sign up button

AR: Spaces before email in field weren't cut and email value wasn't shifted to the begining of the field
ER: Spaces before email in field are cut and email value is shifted to the begining of the field