[ESnext] Implement Object spread

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/assembler.h"
 #include "src/ast/ast-types.h"
 #include "src/ast/ast-value-factory.h"
@@ skipping 1341 matching lines @@
 // Property is used for passing information
 // about an object literal's properties from the parser
 // to the code generator.
 class ObjectLiteralProperty final : public LiteralProperty {
  public:
   enum Kind : uint8_t {
     CONSTANT,              // Property with constant value (compile time).
     COMPUTED,              // Property with computed value (execution time).
     MATERIALIZED_LITERAL,  // Property value is a materialized literal.
     GETTER,
-    SETTER,    // Property is an accessor function.
-    PROTOTYPE  // Property is __proto__.
+    SETTER,     // Property is an accessor function.
+    PROTOTYPE,  // Property is __proto__.
+    SPREAD
   };
 
   Kind kind() const { return kind_; }
 
   // Type feedback information.
   bool IsMonomorphic() const { return !receiver_type_.is_null(); }
   Handle<Map> GetReceiverType() const { return receiver_type_; }
 
   bool IsCompileTimeValue() const;
 
@@ skipping 2234 matching lines @@
                                     : NULL;                                   \
   }
 AST_NODE_LIST(DECLARE_NODE_FUNCTIONS)
 #undef DECLARE_NODE_FUNCTIONS
 
 
 }  // namespace internal
 }  // namespace v8
 
 #endif  // V8_AST_AST_H_