Remove unused 'receiver' field from generators

test/cctest/test-ast-expression-visitor.cc

 // Copyright 2015 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.
 
 #include <stdlib.h>
 
 #include "src/v8.h"
 
 #include "src/ast/ast.h"
 #include "src/ast/ast-expression-visitor.h"
@@ skipping 358 matching lines @@
   CollectTypes(&handles, test_function, &types);
   CHECK_TYPES_BEGIN {
     CHECK_EXPR(FunctionLiteral, Bounds::Unbounded()) {
       // Implicit initial yield
       CHECK_EXPR(Yield, Bounds::Unbounded()) {
         CHECK_VAR(.generator_object, Bounds::Unbounded());
         CHECK_EXPR(Assignment, Bounds::Unbounded()) {
           CHECK_VAR(.generator_object, Bounds::Unbounded());
           CHECK_EXPR(CallRuntime, Bounds::Unbounded()) {
             CHECK_EXPR(ThisFunction, Bounds::Unbounded());
-            CHECK_EXPR(VariableProxy, Bounds::Unbounded());
           }
         }
       }
       // Explicit yield (argument wrapped with CreateIterResultObject)
       CHECK_EXPR(Yield, Bounds::Unbounded()) {
         CHECK_VAR(.generator_object, Bounds::Unbounded());
         CHECK_EXPR(CallRuntime, Bounds::Unbounded()) {
           CHECK_EXPR(Literal, Bounds::Unbounded());
           CHECK_EXPR(Literal, Bounds::Unbounded());
         }
@@ skipping 26 matching lines @@
     CHECK_EXPR(FunctionLiteral, Bounds::Unbounded()) {
       CHECK_EXPR(BinaryOperation, Bounds::Unbounded()) {
         // Skip x + x
         CHECK_SKIP();
         CHECK_EXPR(Literal, Bounds::Unbounded());
       }
     }
   }
   CHECK_TYPES_END
 }