Tests that cache data is correctly deleted by the inspector.

Dumping CacheStorage tree:
    (empty)
Dumping CacheStorage tree:
    cache: testCache1 - http://127.0.0.1:8000/
        (cache empty)
    cache: testCache2 - http://127.0.0.1:8000/
        (cache empty)
Dumping CacheStorage tree:
    cache: testCache1 - http://127.0.0.1:8000/
        0, /1, default, text/plain, 0
        1, /2, default, text/plain, 0
        totalCount: 2
    cache: testCache2 - http://127.0.0.1:8000/
        0, /1, default, text/plain, 0
        1, /2, default, text/plain, 0
        totalCount: 2
Deleting CacheStorage cache testCache2
Dumping CacheStorage tree:
    (empty)