Fix the game screen freezes occasionally even though you hear the sounds

Author: krmbn0576

js/rpg_core/Graphics.js

@@ -161,7 +161,7 @@ Graphics.tickEnd = function() {
  * @param {Stage} stage The stage object to be rendered
  */
 Graphics.render = function(stage) {
-    if (this._skipCount === 0) {
+    if (this._skipCount <= 0) {
         var startTime = Date.now();
         if (stage) {
             this._renderer.render(stage);