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

src/compiler/typer.cc

Index: src/compiler/typer.cc
diff --git a/src/compiler/typer.cc b/src/compiler/typer.cc
index 15bc6dfba24becd2388b947c295f72ebc44ad7bd..e33b7764567881f149e760262b26a9a58f2b1f87 100644
--- a/src/compiler/typer.cc
+++ b/src/compiler/typer.cc
@@ -295,7 +295,6 @@
 
   static Type* ReferenceEqualTyper(Type*, Type*, Typer*);
   static Type* StringFromCharCodeTyper(Type*, Typer*);
-  static Type* StringFromCodePointTyper(Type*, Typer*);
 
   Reduction UpdateType(Node* node, Type* current) {
     if (NodeProperties::IsTyped(node)) {
@@ -1366,10 +1365,6 @@
         case kStringToLowerCase:
         case kStringToUpperCase:
           return Type::String();
-
-        case kStringIteratorNext:
-          return Type::OtherObject();
-
         // Array functions.
         case kArrayIndexOf:
         case kArrayLastIndexOf:
@@ -1556,19 +1551,6 @@
   return Type::String();
 }
 
-Type* Typer::Visitor::StringFromCodePointTyper(Type* type, Typer* t) {
-  type = NumberToUint32(ToNumber(type, t), t);
-  Factory* f = t->isolate()->factory();
-  double min = type->Min();
-  double max = type->Max();
-  if (min == max) {
-    uint32_t code = static_cast<uint32_t>(min) & String::kMaxUtf16CodeUnitU;
-    Handle<String> string = f->LookupSingleCharacterStringFromCode(code);
-    return Type::Constant(string, t->zone());
-  }
-  return Type::String();
-}
-
 Type* Typer::Visitor::TypeStringCharCodeAt(Node* node) {
   // TODO(bmeurer): We could do better here based on inputs.
   return Type::Range(0, kMaxUInt16, zone());
@@ -1576,10 +1558,6 @@
 
 Type* Typer::Visitor::TypeStringFromCharCode(Node* node) {
   return TypeUnaryOp(node, StringFromCharCodeTyper);
-}
-
-Type* Typer::Visitor::TypeStringFromCodePoint(Node* node) {
-  return TypeUnaryOp(node, StringFromCodePointTyper);
 }
 
 Type* Typer::Visitor::TypeCheckBounds(Node* node) {