[parser] parenthesized Literals are not valid AssignmentPatterns

src/parsing/preparser.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_PARSING_PREPARSER_H
 #define V8_PARSING_PREPARSER_H
 
 #include "src/ast/scopes.h"
 #include "src/bailout-reason.h"
 #include "src/hashmap.h"
@@ skipping 261 matching lines @@
   // and PreParser.
   PreParserExpression* operator->() { return this; }
 
   // More dummy implementations of things PreParser doesn't need to track:
   void set_index(int index) {}  // For YieldExpressions
   void set_should_eager_compile() {}
 
   int position() const { return RelocInfo::kNoPosition; }
   void set_function_token_position(int position) {}
 
+  // Parenthesized expressions in the form `( Expression )`.
+  void set_is_parenthesized() {
+    code_ = ParenthesizedField::update(code_, true);
+  }
+  bool is_parenthesized() const { return ParenthesizedField::decode(code_); }
+
  private:
   enum Type {
     kExpression,
     kIdentifierExpression,
     kStringLiteralExpression,
     kBinaryOperationExpression,
     kSpreadExpression,
     kObjectLiteralExpression,
     kArrayLiteralExpression
   };
 
   enum ExpressionType {
     kThisExpression,
     kThisPropertyExpression,
     kPropertyExpression,
     kCallExpression,
     kSuperCallReference,
     kNoTemplateTagExpression,
     kAssignment
   };
 
   explicit PreParserExpression(uint32_t expression_code)
       : code_(expression_code) {}
 
   // The first three bits are for the Type.
   typedef BitField<Type, 0, 3> TypeField;
 
+  // The high order bit applies only to nodes which would inherit from the
+  // Expression ASTNode --- This is by necessity, due to the fact that
+  // Expression nodes may be represented as multiple Types, not exclusively
+  // through kExpression.
+  // TODO(caitp, adamk): clean up PreParserExpression bitfields.
+  typedef BitField<bool, 31, 1> ParenthesizedField;
+
   // The rest of the bits are interpreted depending on the value
   // of the Type field, so they can share the storage.
   typedef BitField<ExpressionType, TypeField::kNext, 3> ExpressionTypeField;
   typedef BitField<bool, TypeField::kNext, 1> IsUseStrictField;
   typedef BitField<bool, IsUseStrictField::kNext, 1> IsUseStrongField;
   typedef BitField<PreParserIdentifier::Type, TypeField::kNext, 10>
       IdentifierTypeField;
   typedef BitField<bool, TypeField::kNext, 1> HasCoverInitializedNameField;
 
   uint32_t code_;
@@ skipping 807 matching lines @@
     const PreParserFormalParameters& parameters, FunctionKind kind,
     FunctionLiteral::FunctionType function_type, bool* ok) {
   return pre_parser_->ParseEagerFunctionBody(function_name, pos, parameters,
                                              kind, function_type, ok);
 }
 
 }  // namespace internal
 }  // namespace v8
 
 #endif  // V8_PARSING_PREPARSER_H