Fix stale EG(opline_before_exception) pointer through eval

[iluuu1994]

Fixes GH-20183

[arnaud-lb]

The same change needs to be applied to zend_generator_dtor_storage():

function gen() {
    try {
        yield 1;
    } finally {
        eval('try { throw new Error(); } catch (Error) {}');
        debug_print_backtrace();
    }
}

class A {
    private $gen;
    function __construct() {
        $this->gen = gen();
        $this->gen->rewind();
    }
}

B::$a = new A();

This looks right to me otherwise.

[iluuu1994]

Good catch. Let me go through all instances of EG(exception) = NULL;.