Expected behavior
Must validate the field before entering the user
Actual behavior
Even though user clear the username from the textbox using (x) button, Can add the user by clicking the ADD button
Steps to reproduce the problem
- Open the sites
- Login as a valid user (pat_monahan)
- In the Projects
- Click on a Project name
- Click Dashboard
- Click Add New team member
- Select a user
- Click (x) clear button
- Click ADD
Screenshot/Screencast/JS Log (If not attached here, Please check the comment section)

Environment
- Device(s): Laptop
- Browser(s): Chrome 53.0.2785.116 m, FF 49.0.1
- Operating System: Windows 7 Pro 64bit
- User Accounts: pat_monahan
- User Role: Manager