Bump to v4.16.0.

_stackDelete.js

@@ -8,7 +8,11 @@
  * @returns {boolean} Returns `true` if the entry was removed, else `false`.
  */
 function stackDelete(key) {
-  return this.__data__['delete'](key);
+  var data = this.__data__,
+      result = data['delete'](key);
+
+  this.size = data.size;
+  return result;
 }
 
 module.exports = stackDelete;