[ast] Clean up a few unnecessary bits in AST

src/ast/ast.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_AST_AST_H_
 #define V8_AST_AST_H_
 
 #include "src/ast/ast-value-factory.h"
 #include "src/ast/modules.h"
 #include "src/ast/variables.h"
@@ skipping 202 matching lines @@
 
  protected:
   AstNode(int position, NodeType type)
       : position_(position), node_type_(type) {}
 
  private:
   // Hidden to prevent accidental usage. It would have to load the
   // current zone from the TLS.
   void* operator new(size_t size);
 
-  friend class CaseClause;  // Generates AST IDs.
-
   int position_;
   NodeType node_type_;
   // Ends with NodeType which is uint8_t sized. Deriving classes in turn begin
   // sub-int32_t-sized fields for optimum packing efficiency.
 };
 
 
 class Statement : public AstNode {
  public:
   bool IsEmpty() { return AsEmptyStatement() != NULL; }
@@ skipping 1338 matching lines @@
   ZoneList<Expression*>* values_;
 };
 
 
 class VariableProxy final : public Expression {
  public:
   bool IsValidReferenceExpression() const {
     return !is_this() && !is_new_target();
   }
 
-  bool IsArguments() const { return is_resolved() && var()->is_arguments(); }
-
   Handle<String> name() const { return raw_name()->string(); }
   const AstRawString* raw_name() const {
     return is_resolved() ? var_->raw_name() : raw_name_;
   }
 
   Variable* var() const {
     DCHECK(is_resolved());
     return var_;
   }
   void set_var(Variable* v) {
@@ skipping 49 matching lines @@
   VariableProxy(Zone* zone, const VariableProxy* copy_from);
 
   static int parent_num_ids() { return Expression::num_ids(); }
   int local_id(int n) const { return base_id() + parent_num_ids() + n; }
 
   class IsThisField : public BitField8<bool, 0, 1> {};
   class IsAssignedField : public BitField8<bool, 1, 1> {};
   class IsResolvedField : public BitField8<bool, 2, 1> {};
   class IsNewTargetField : public BitField8<bool, 3, 1> {};
 
-  // Start with 16-bit (or smaller) field, which should get packed together
-  // with Expression's trailing 16-bit field.
   uint8_t bit_field_;
   // Position is stored in the AstNode superclass, but VariableProxy needs to
   // know its end position too (for error messages). It cannot be inferred from
   // the variable name length because it can contain escapes.
   int end_position_;
   FeedbackVectorSlot variable_feedback_slot_;
   union {
     const AstRawString* raw_name_;  // if !is_resolved_
     Variable* var_;                 // if is_resolved_
   };
@@ skipping 1812 matching lines @@
                                     : NULL;                                   \
   }
 AST_NODE_LIST(DECLARE_NODE_FUNCTIONS)
 #undef DECLARE_NODE_FUNCTIONS
 
 
 }  // namespace internal
 }  // namespace v8
 
 #endif  // V8_AST_AST_H_