Braceless anonymous function scopes are not always closed

[Gama11]

The grammar relies on a ; to close function scopes when there are no braces. However, for instance inside of function arguments, like in the following example, it doesn't ever get to match against the ;:

class C {
    function f() {
        f(
            function() f,
            function() f,
            function() f
        );
    }
}

As a result, there are too many function scopes on the stack that won't ever be closed:

This causes subsequent highlighting to break in some cases, for instance the type name T here:

[nadako]

Check if fixing this also fixes #23 :)

[back2dos]

Hmm. It looks to me like arrow functions cause no such issues. Could their syntax definition be used as a basis for anonymous functions?