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

src/globals.h

Index: src/globals.h
diff --git a/src/globals.h b/src/globals.h
index eb899469fe544977e4e1392ad5e9aa9d811bbbc6..7ef581962cfea836034d82bec132b74775ece7a2 100644
--- a/src/globals.h
+++ b/src/globals.h
@@ -1233,6 +1233,12 @@ enum LiveEditFrameDropMode {
   LIVE_EDIT_CURRENTLY_SET_MODE
 };
 
+enum class UnicodeEncoding {
+  // Different unicode encodings in a |word32|:
+  UTF16,  // hi 16bits -> trailing surrogate or 0, low 16bits -> lead surrogate
+  UTF32,  // full UTF32 code unit / Unicode codepoint
+};
+
 }  // namespace internal
 }  // namespace v8