Fix GH-21768: ext/reflection: assertion failure on internal virtual properties.

ReflectionProperty::isReadable() and isWritable() asserted prop->hooks
being set whenever ZEND_ACC_VIRTUAL is set. Internal classes such as
DOMDocument declare virtual properties backed by the object read/write
handlers without hooks, tripping the assertion.

Assertion introduced in e4f727d.

Author: devnexen

ext/reflection/php_reflection.c

@@ -6763,8 +6763,7 @@ ZEND_METHOD(ReflectionProperty, isReadable)
 	}
 
 	if (prop->flags & ZEND_ACC_VIRTUAL) {
-		ZEND_ASSERT(prop->hooks);
-		if (!prop->hooks[ZEND_PROPERTY_HOOK_GET]) {
+		if (prop->hooks && !prop->hooks[ZEND_PROPERTY_HOOK_GET]) {
 			RETURN_FALSE;
 		}
 	} else if (obj && (!prop->hooks || !prop->hooks[ZEND_PROPERTY_HOOK_GET])) {
@@ -6855,8 +6854,7 @@ ZEND_METHOD(ReflectionProperty, isWritable)
 	}
 
 	if (prop->flags & ZEND_ACC_VIRTUAL) {
-		ZEND_ASSERT(prop->hooks);
-		if (!prop->hooks[ZEND_PROPERTY_HOOK_SET]) {
+		if (prop->hooks && !prop->hooks[ZEND_PROPERTY_HOOK_SET]) {
 			RETURN_FALSE;
 		}
 	} else if (obj && (prop->flags & ZEND_ACC_READONLY)) {