[generators] Desugar yield*.

src/parsing/parser-base.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_PARSER_BASE_H
 #define V8_PARSING_PARSER_BASE_H
 
 #include "src/ast/scopes.h"
 #include "src/bailout-reason.h"
 #include "src/hashmap.h"
@@ skipping 2128 matching lines @@
         DCHECK_EQ(Yield::kDelegating, kind);
         // Delegating yields require an RHS; fall through.
       default:
         expression = ParseAssignmentExpression(false, classifier, CHECK_OK);
         expression =
             Traits::RewriteNonPattern(expression, classifier, CHECK_OK);
         break;
     }
   }
   if (kind == Yield::kDelegating) {
-    // var iterator = subject[Symbol.iterator]();
-    // Hackily disambiguate o from o.next and o [Symbol.iterator]().
-    // TODO(verwaest): Come up with a better solution.
-    expression = this->GetIterator(expression, factory(), pos + 1);
+    return Traits::RewriteYieldStar(generator_object, expression, pos);
   }
   // Hackily disambiguate o from o.next and o [Symbol.iterator]().
   // TODO(verwaest): Come up with a better solution.
   typename Traits::Type::YieldExpression yield =
       factory()->NewYield(generator_object, expression, kind, pos);
   return yield;
 }
 
 
 // Precedence = 3
@@ skipping 1201 matching lines @@
       return;
     }
     has_seen_constructor_ = true;
     return;
   }
 }
 }  // namespace internal
 }  // namespace v8
 
 #endif  // V8_PARSING_PARSER_BASE_H