[ExpressionLanguage] Strict in_array check in Parser.php

| Q             | A
| ------------- | ---
| Bug fix?      | yes
| New feature?  | no
| BC breaks?    | no
| Deprecations? | no
| Tests pass?   | yes
| Fixed tickets | 
| License       | MIT
| Doc PR        | 

Otherwise it doesn't throw an exception for the cases when passed parameters array includes zero key (and that will result in the PHP Notice down the road).