Remove --promise-extra flag

src/contexts.h

 // Copyright 2012 the V8 project authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #ifndef V8_CONTEXTS_H_
 #define V8_CONTEXTS_H_
 
 #include "src/heap/heap.h"
 #include "src/objects.h"
 
@@ skipping 63 matching lines @@
   V(ERROR_TO_STRING, JSFunction, error_to_string)                           \
   V(EVAL_ERROR_FUNCTION_INDEX, JSFunction, eval_error_function)             \
   V(GLOBAL_EVAL_FUN_INDEX, JSFunction, global_eval_fun)                     \
   V(MAP_DELETE_METHOD_INDEX, JSFunction, map_delete)                        \
   V(MAP_GET_METHOD_INDEX, JSFunction, map_get)                              \
   V(MAP_HAS_METHOD_INDEX, JSFunction, map_has)                              \
   V(MAP_SET_METHOD_INDEX, JSFunction, map_set)                              \
   V(OBJECT_VALUE_OF, JSFunction, object_value_of)                           \
   V(OBJECT_TO_STRING, JSFunction, object_to_string)                         \
   V(PROMISE_CATCH_INDEX, JSFunction, promise_catch)                         \
-  V(PROMISE_CHAIN_INDEX, JSFunction, promise_chain)                         \
   V(PROMISE_CREATE_INDEX, JSFunction, promise_create)                       \
   V(PROMISE_FUNCTION_INDEX, JSFunction, promise_function)                   \
   V(PROMISE_HAS_USER_DEFINED_REJECT_HANDLER_INDEX, JSFunction,              \
     promise_has_user_defined_reject_handler)                                \
   V(PROMISE_REJECT_INDEX, JSFunction, promise_reject)                       \
   V(PROMISE_RESOLVE_INDEX, JSFunction, promise_resolve)                     \
   V(PROMISE_CREATE_RESOLVED_INDEX, JSFunction, promise_create_resolved)     \
   V(PROMISE_CREATE_REJECTED_INDEX, JSFunction, promise_create_rejected)     \
   V(PROMISE_THEN_INDEX, JSFunction, promise_then)                           \
   V(RANGE_ERROR_FUNCTION_INDEX, JSFunction, range_error_function)           \
@@ skipping 436 matching lines @@
 #endif
 
   STATIC_ASSERT(kHeaderSize == Internals::kContextHeaderSize);
   STATIC_ASSERT(EMBEDDER_DATA_INDEX == Internals::kContextEmbedderDataIndex);
 };
 
 }  // namespace internal
 }  // namespace v8
 
 #endif  // V8_CONTEXTS_H_