Revert of [builtins] Move StringNormalize to a cpp builtin.

src/builtins/builtins-string.cc

Index: src/builtins/builtins-string.cc
diff --git a/src/builtins/builtins-string.cc b/src/builtins/builtins-string.cc
index 88035f8d36f7c42667a225f35dd4455248fe9afb..d38f6b069d50f5e751d7dfb3147f602a25b2d4f6 100644
--- a/src/builtins/builtins-string.cc
+++ b/src/builtins/builtins-string.cc
@@ -477,40 +477,6 @@
   assembler->Return(result);
 }
 
-// ES6 section 21.1.3.12 String.prototype.normalize ( [form] )
-//
-// Simply checks the argument is valid and returns the string itself.
-// If internationalization is enabled, then i18n.js will override this function
-// and provide the proper functionality, so this is just a fallback.
-BUILTIN(StringPrototypeNormalize) {
-  HandleScope handle_scope(isolate);
-  TO_THIS_STRING(string, "String.prototype.normalize");
-
-  Handle<Object> form_input = args.atOrUndefined(isolate, 1);
-  if (form_input->IsUndefined(isolate)) return *string;
-
-  Handle<String> form;
-  ASSIGN_RETURN_FAILURE_ON_EXCEPTION(isolate, form,
-                                     Object::ToString(isolate, form));
-
-  if (!(String::Equals(form,
-                       isolate->factory()->NewStringFromStaticChars("NFC")) ||
-        String::Equals(form,
-                       isolate->factory()->NewStringFromStaticChars("NFD")) ||
-        String::Equals(form,
-                       isolate->factory()->NewStringFromStaticChars("NFKC")) ||
-        String::Equals(form,
-                       isolate->factory()->NewStringFromStaticChars("NFKD")))) {
-    Handle<String> valid_forms =
-        isolate->factory()->NewStringFromStaticChars("NFC, NFD, NFKC, NFKD");
-    THROW_NEW_ERROR_RETURN_FAILURE(
-        isolate,
-        NewRangeError(MessageTemplate::kNormalizationForm, valid_forms));
-  }
-
-  return *string;
-}
-
 // ES6 section 21.1.3.25 String.prototype.toString ()
 void Builtins::Generate_StringPrototypeToString(CodeStubAssembler* assembler) {
   typedef compiler::Node Node;