delete
The delete() method of the Cache interface finds the Cache entry whose key is the request, and if found, deletes the Cache entry and returns a Promise that resolves to true. If no Cache entry is found, it resolves to false.
The delete() method of the CacheStorage interface finds the Cache object matching the cacheName, and if found, deletes the Cache object and returns a Promise that resolves to true. If no Cache object is found, it resolves to false.