Remove PROHIBITS_OVERWRITING as it is subsumed by non-configurable properties.

src/objects-inl.h

Index: src/objects-inl.h
diff --git a/src/objects-inl.h b/src/objects-inl.h
index 29fcec6017a29ec87ce8e352de6690c33c78c1dd..abbd1dba2fa409b7ac15dd1bb0a942e958c74289 100644
--- a/src/objects-inl.h
+++ b/src/objects-inl.h
@@ -6393,16 +6393,6 @@ void AccessorInfo::set_all_can_write(bool value) {
 }
 
 
-bool AccessorInfo::prohibits_overwriting() {
-  return BooleanBit::get(flag(), kProhibitsOverwritingBit);
-}
-
-
-void AccessorInfo::set_prohibits_overwriting(bool value) {
-  set_flag(BooleanBit::set(flag(), kProhibitsOverwritingBit, value));
-}
-
-
 PropertyAttributes AccessorInfo::property_attributes() {
   return AttributesField::decode(static_cast<uint32_t>(flag()->value()));
 }
@@ -6428,9 +6418,6 @@ void ExecutableAccessorInfo::clear_setter() {
 void AccessorPair::set_access_flags(v8::AccessControl access_control) {
   int current = access_flags()->value();
   current = BooleanBit::set(current,
-                            kProhibitsOverwritingBit,
-                            access_control & PROHIBITS_OVERWRITING);
-  current = BooleanBit::set(current,
                             kAllCanReadBit,
                             access_control & ALL_CAN_READ);
   current = BooleanBit::set(current,
@@ -6450,11 +6437,6 @@ bool AccessorPair::all_can_write() {
 }
 
 
-bool AccessorPair::prohibits_overwriting() {
-  return BooleanBit::get(access_flags(), kProhibitsOverwritingBit);
-}
-
-
 template<typename Derived, typename Shape, typename Key>
 void Dictionary<Derived, Shape, Key>::SetEntry(int entry,
                                                Handle<Object> key,