Select Button error when options are not defined

[arjunshankar]

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Plunkr Case (Bug Reports)
https://stackblitz.com/edit/angular-z6zum3

Current behavior

1. use SelectButton with custom template - as explained in the docs.
2. data is provided to selectButton on demand.
3. following error seen in console.
   ERROR TypeError: Cannot read property 'length' of undefined
   at Object.eval [as updateDirectives] (SelectButton.html:2)
4. the error is not seen if not using a custome template

Expected behavior

1. there shouldn't be any error.

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

1. breaks the flow momentarily.

Please tell us about your environment:

• Angular version: 6.0

• PrimeNG version: 5.2.7

• Browser: [all | Chrome XX | Firefox XX | IE XX | Safari XX | Mobile Chrome XX | Android X.X Web Browser | iOS XX Safari | iOS XX UIWebView | iOS XX WKWebView ]

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

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

[arjunshankar]

Thanks for the quick turn around....