[turbofan] inline %StringIteratorPrototype%.next in JSBuiltinReducer.

src/compiler/access-builder.h

Index: src/compiler/access-builder.h
diff --git a/src/compiler/access-builder.h b/src/compiler/access-builder.h
index 7cc1fe18bd03104c8eafe51cf21ca15e319ddacf..45acb8d38a78a475a4fae39329ddd1b2ff0376f7 100644
--- a/src/compiler/access-builder.h
+++ b/src/compiler/access-builder.h
@@ -175,6 +175,7 @@ class AccessBuilder final : public AllStatic {
 
   // Provides access to SeqTwoByteString characters.
   static ElementAccess ForSeqTwoByteStringCharacter();
+  static FieldAccess ForSeqTwoByteStringFirstCharacterPair();
 
   // Provides access to JSGlobalObject::global_proxy() field.
   static FieldAccess ForJSGlobalObjectGlobalProxy();
@@ -182,6 +183,12 @@ class AccessBuilder final : public AllStatic {
   // Provides access to JSGlobalObject::native_context() field.
   static FieldAccess ForJSGlobalObjectNativeContext();
 
+  // Provides access to JSStringIterator::string() field.
+  static FieldAccess ForJSStringIteratorString();
+
+  // Provides access to JSStringIterator::index() field.
+  static FieldAccess ForJSStringIteratorIndex();
+
   // Provides access to JSValue::value() field.
   static FieldAccess ForValue();