Move generator-close on exception from the generator function to the GeneratorResume builtin.

src/parsing/parser.h

Index: src/parsing/parser.h
diff --git a/src/parsing/parser.h b/src/parsing/parser.h
index 7eb75fde3349f7854ca8c42ce7be052e57db3487..257547c2d223bffab83213601255da084699783e 100644
--- a/src/parsing/parser.h
+++ b/src/parsing/parser.h
@@ -352,6 +352,9 @@ class V8_EXPORT_PRIVATE Parser : public NON_EXPORTED_BASE(ParserBase<Parser>) {
   void ParseAndRewriteGeneratorFunctionBody(int pos, FunctionKind kind,
                                             ZoneList<Statement*>* body,
                                             bool* ok);
+  void ParseAndRewriteAsyncGeneratorFunctionBody(int pos, FunctionKind kind,
+                                                 ZoneList<Statement*>* body,
+                                                 bool* ok);
   void CreateFunctionNameAssignment(const AstRawString* function_name, int pos,
                                     FunctionLiteral::FunctionType function_type,
                                     DeclarationScope* function_scope,
@@ -874,8 +877,6 @@ class V8_EXPORT_PRIVATE Parser : public NON_EXPORTED_BASE(ParserBase<Parser>) {
   Expression* BuildUnaryExpression(Expression* expression, Token::Value op,
                                    int pos);
 
-  Expression* BuildIteratorResult(Expression* value, bool done);
-
   // Generate AST node that throws a ReferenceError with the given type.
   V8_INLINE Expression* NewThrowReferenceError(
       MessageTemplate::Template message, int pos) {