ext/session: refactor session_write_close()

By making the underlying function return a bool and not do duplicate checks

UPGRADING.INTERNALS

@@ -97,6 +97,9 @@ PHP 8.6 INTERNALS UPGRADE NOTES
   . Dropped session_options parameter from all methods in mysqlnd_auth.
     The same information is present in conn->options and should be used instead.
 
+- ext/session:
+  . php_session_flush() now returns a bool rather than a zend_result.
+
 - ext/standard:
   . _php_error_log() now has a formal return type of zend_result.
   . _php_error_log() now accepts zend_string* values instead of char*.

ext/session/php_session.h

@@ -263,7 +263,7 @@ PHPAPI zend_result php_session_register_serializer(const char *name,
 	        zend_result (*decode)(PS_SERIALIZER_DECODE_ARGS));
 
 PHPAPI zend_result php_session_start(void);
-PHPAPI zend_result php_session_flush(bool write);
+PHPAPI bool php_session_flush(bool write);
 PHPAPI php_session_status php_get_session_status(void);
 
 PHPAPI const ps_module *_php_find_ps_module(const char *name);

ext/session/session.c

@@ -1720,14 +1720,14 @@ PHPAPI zend_result php_session_start(void)
 	return SUCCESS;
 }
 
-PHPAPI zend_result php_session_flush(bool write)
+PHPAPI bool php_session_flush(bool write)
 {
 	if (PS(session_status) == php_session_active) {
 		php_session_save_current_state(write);
 		PS(session_status) = php_session_none;
-		return SUCCESS;
+		return true;
 	}
-	return FAILURE;
+	return false;
 }
 
 PHPAPI php_session_status php_get_session_status(void)
@@ -2724,11 +2724,7 @@ PHP_FUNCTION(session_write_close)
 		RETURN_THROWS();
 	}
 
-	if (PS(session_status) != php_session_active) {
-		RETURN_FALSE;
-	}
-	php_session_flush(true);
-	RETURN_TRUE;
+	RETURN_BOOL(php_session_flush(true));
 }
 
 /* Abort session and end session. Session data will not be written */