RouterLinkActive in tabMenu not applied to the li element.

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Plunkr Case (Bug Reports)
http://embed.plnkr.co/lDZAZniVKAdDB3n9PRF2/
Click goto B and you can see that first <li> still has ui-state-active class.

Current behavior
When using tabMenu activeItem add active class to the <li> element. But routerLinkActive add active class to the <a> element.

Expected behavior
RouterLinkActive directive set active class to the <li> element as well.

Minimal reproduction of the problem with instructions

• Angular version: 4.4.3

• PrimeNG version: 4.2.1

• Browser: all