Avoid temporary Vectors for arrow function parameter lists

src/parser.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_PARSER_H_
 #define V8_PARSER_H_
 
 #include "src/allocation.h"
 #include "src/ast.h"
 #include "src/compiler.h"  // For CachedDataMode
@@ skipping 532 matching lines @@
   }
   ZoneList<ObjectLiteral::Property*>* NewPropertyList(int size, Zone* zone) {
     return new(zone) ZoneList<ObjectLiteral::Property*>(size, zone);
   }
   ZoneList<v8::internal::Statement*>* NewStatementList(int size, Zone* zone) {
     return new(zone) ZoneList<v8::internal::Statement*>(size, zone);
   }
   V8_INLINE Scope* NewScope(Scope* parent_scope, ScopeType scope_type);
 
   // Utility functions
-  Vector<VariableProxy*> ParameterListFromExpression(Expression* expression,
-                                                     bool* ok);
+  unsigned DeclareArrowParametersFromExpression(Expression* expression,
+                                                Scope* scope,
+                                                Scanner::Location* dupe_loc,
+                                                bool* ok);
   V8_INLINE AstValueFactory* ast_value_factory();
 
   // Temporary glue; these functions will move to ParserBase.
   Expression* ParseV8Intrinsic(bool* ok);
   FunctionLiteral* ParseFunctionLiteral(
       const AstRawString* name,
       Scanner::Location function_name_location,
       bool name_is_strict_reserved,
       bool is_generator,
       int function_token_position,
@@ skipping 309 matching lines @@
  private:
   static const int kLiteralTypeSlot = 0;
   static const int kElementsSlot = 1;
 
   DISALLOW_IMPLICIT_CONSTRUCTORS(CompileTimeValue);
 };
 
 } }  // namespace v8::internal
 
 #endif  // V8_PARSER_H_