remove debug code

fix bug: scene builder build twice when compositeFrame

Runtime/rendering/view.cs

 
         public void compositeFrame() {
             var builder = new SceneBuilder();
-            this.layer.buildScene(builder);
-            using (var scene = builder.build()) {
+            using (var scene = this.layer.buildScene(builder)) {
                 Window.instance.render(scene);
             }
 

Runtime/ui/utils/renderer/allocUtils/debug.cs

     
     public static class AllocDebugger {
 
-        public const bool enableDebugging = true;
+        public const bool enableDebugging = false;
 
         static int allocCount = 0;
         

Runtime/ui/utils/renderer/allocUtils/uipath_cache_manager.cs

 using System.Collections.Generic;
-using UnityEngine;
 
 namespace Unity.UIWidgets.ui {