PEAR.Functions.FunctionCallSignature false positive for array of functions

[VincentLanglet]

The following code

$a = ['a' => function ($b) { return $b; }];
$a['a']( 1 );

Return no error for the extra space after the opening and before the closing parentheses.

Since the ( is correctly ignored in the Generic.WhiteSpace.ArbitraryParenthesesSpacing, this should be handle in the FunctionCallSignatureSniff.