[private brand checks] Remove --harmony-private-brand-checks

Private brand checks have shipped since M91.

Bug: v8:11374
Change-Id: Ifd2f8e9904cdb25b45b2e4019da13b3cfc9efdc5
Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/3622266Reviewed-by: Marja Hölttä <marja@chromium.org>
Commit-Queue: Shu-yu Guo <syg@chromium.org>
Auto-Submit: Shu-yu Guo <syg@chromium.org>
Cr-Commit-Position: refs/heads/main@{#80455}

src/flags/flag-definitions.h

@@ -329,7 +329,6 @@ DEFINE_BOOL(harmony_shipping, true, "enable all shipped harmony features")
 #define HARMONY_SHIPPING_BASE(V)                                      \
   V(harmony_sharedarraybuffer, "harmony sharedarraybuffer")           \
   V(harmony_atomics, "harmony atomics")                               \
-  V(harmony_private_brand_checks, "harmony private brand checks")     \
   V(harmony_error_cause, "harmony error cause property")              \
   V(harmony_object_has_own, "harmony Object.hasOwn")                  \
   V(harmony_class_static_blocks, "harmony static initializer blocks") \

src/init/bootstrapper.cc

@@ -4479,7 +4479,6 @@ void Genesis::InitializeConsole(Handle<JSObject> extras_binding) {
   void Genesis::InitializeGlobal_##id() {}
 
 EMPTY_INITIALIZE_GLOBAL_FOR_FEATURE(harmony_import_assertions)
-EMPTY_INITIALIZE_GLOBAL_FOR_FEATURE(harmony_private_brand_checks)
 EMPTY_INITIALIZE_GLOBAL_FOR_FEATURE(harmony_class_static_blocks)
 EMPTY_INITIALIZE_GLOBAL_FOR_FEATURE(harmony_error_cause)
 

src/interpreter/bytecode-generator.cc

@@ -6200,7 +6200,6 @@ void BytecodeGenerator::VisitCompareOperation(CompareOperation* expr) {
     BuildLiteralCompareNil(expr->op(), BytecodeArrayBuilder::kNullValue);
   } else {
     if (expr->op() == Token::IN && expr->left()->IsPrivateName()) {
-      DCHECK(FLAG_harmony_private_brand_checks);
       Variable* var = expr->left()->AsVariableProxy()->var();
       if (IsPrivateMethodOrAccessorVariableMode(var->mode())) {
         BuildPrivateMethodIn(var, expr->right());

src/parsing/parser-base.h

@@ -3241,8 +3241,7 @@ typename ParserBase<Impl>::ExpressionT ParserBase<Impl>::ParseBinaryExpression(
 
   // "#foo in ShiftExpression" needs to be parsed separately, since private
   // identifiers are not valid PrimaryExpressions.
-  if (V8_UNLIKELY(FLAG_harmony_private_brand_checks &&
-                  peek() == Token::PRIVATE_NAME)) {
+  if (V8_UNLIKELY(peek() == Token::PRIVATE_NAME)) {
     ExpressionT x = ParsePropertyOrPrivatePropertyName();
     int prec1 = Token::Precedence(peek(), accept_IN_);
     if (peek() != Token::IN || prec1 < prec) {