Hide NativeStackTrace things (#12266)

std/hl/_std/haxe/NativeStackTrace.hx

@@ -4,6 +4,7 @@ import hl.NativeArray;
 import hl.Bytes;
 import haxe.CallStack.StackItem;
 
+@:dox(hide)
 typedef Symbol = #if (hl_ver >= version("1.12.0")) hl.Abstract<"hl_symbol"> #else hl.Bytes #end
 
 /**

std/js/_std/haxe/NativeStackTrace.hx

@@ -10,7 +10,7 @@ private extern class V8Error {
 	static var prepareStackTrace:(error:Error, structuredStackTrace:Array<V8CallSite>)->Any;
 }
 
-typedef V8CallSite = {
+private typedef V8CallSite = {
 	function getFunctionName():String;
 	function getFileName():String;
 	function getLineNumber():Int;