Remove dead feature macro.

The opt-out code was removed some time ago.

PiperOrigin-RevId: 631826723

src/google/protobuf/port_def.inc

@@ -597,13 +597,6 @@ static_assert(PROTOBUF_ABSL_MIN(20230125, 3),
 #define PROTOBUF_TSAN_DECLARE_MEMBER
 #endif
 
-#ifdef PROTOBUF_USE_TABLE_PARSER_ON_REFLECTION
-#error PROTOBUF_USE_TABLE_PARSER_ON_REFLECTION was previously defined
-#endif
-#if !defined(PROTOBUF_TEMPORARY_DISABLE_TABLE_PARSER_ON_REFLECTION)
-#define PROTOBUF_USE_TABLE_PARSER_ON_REFLECTION 1
-#endif  // PROTOBUF_ENABLE_FORCE_ALLOCATION_ON_CONSTRUCTION
-
 // Note that this is performance sensitive: changing the parameters will change
 // the registers used by the ABI calling convention, which subsequently affects
 // register selection logic inside the function.

src/google/protobuf/port_undef.inc

@@ -65,7 +65,6 @@
 #undef PROTOBUF_MSAN
 #undef PROTOBUF_TSAN
 #undef PROTOBUF_TSAN_DECLARE_MEMBER
-#undef PROTOBUF_USE_TABLE_PARSER_ON_REFLECTION
 #undef PROTOBUF_BUILTIN_CONSTANT_P
 #undef PROTOBUF_DESCRIPTOR_WEAK_MESSAGES_ALLOWED
 #undef PROTOBUF_PREFETCH_PARSE_TABLE