Autocomplete control does not validate properly when you empty the control

[BobFleischman]

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Current behavior

When we start to type and then empty the field it does not throw the 'Required' error.

Expected behavior

It should throw the required error.

Minimal reproduction of the problem with instructions

Set up an autocomplete with form builder and a Required validator. Select something and then delete it.

What is the motivation / use case for changing the behavior?

Please tell us about your environment:

Windows, Visual Studio Code

• Angular version: 6 and 7

• PrimeNG version: 6.X and 7X

• Browser: Chrome XX | Firefox XX | IE XX |

• Language: [all | TypeScript X.X | ES6/7 | ES5]

• Node (for AoT issues): node --version =

[cagataycivici]

Fixed via PR