fixup! lib: implement WeakReference on top of JS WeakRef

Author: joyeecheung

lib/internal/util.js

@@ -799,33 +799,34 @@ function guessHandleType(fd) {
 }
 
 class WeakReference {
+  #weak = null;
+  #strong = null;
+  #refCount = 0;
   constructor(object) {
-    this.weak = new SafeWeakRef(object);
-    this.strong = null;
-    this.refCount = 0;
+    this.#weak = new SafeWeakRef(object);
   }
 
   incRef() {
-    this.refCount++;
-    if (this.refCount === 1) {
-      const derefed = this.weak.deref();
+    this.#refCount++;
+    if (this.#refCount === 1) {
+      const derefed = this.#weak.deref();
       if (derefed !== undefined) {
-        this.strong = derefed;
+        this.#strong = derefed;
       }
     }
-    return this.refCount;
+    return this.#refCount;
   }
 
   decRef() {
-    this.refCount--;
-    if (this.refCount === 0) {
-      this.strong = null;
+    this.#refCount--;
+    if (this.#refCount === 0) {
+      this.#strong = null;
     }
-    return this.refCount;
+    return this.#refCount;
   }
 
   get() {
-    return this.weak.deref();
+    return this.#weak.deref();
   }
 }