All private symbols are own symbols

src/factory.h

Index: src/factory.h
diff --git a/src/factory.h b/src/factory.h
index cd00487c7a397418bf1aa4b42f175a33247b559d..2de768bf138e328518ab5108c6086eff74556650 100644
--- a/src/factory.h
+++ b/src/factory.h
@@ -225,8 +225,7 @@ class Factory final {
 
   // Create a symbol.
   Handle<Symbol> NewSymbol();
-  Handle<Symbol> NewPrivateSymbol();
-  Handle<Symbol> NewPrivateOwnSymbol(Handle<Object> name);
+  Handle<Symbol> NewPrivateSymbol(Handle<Object> name);
 
   // Create a global (but otherwise uninitialized) context.
   Handle<Context> NewNativeContext();