Tests IndexedDB tree element on resources panel.

Expanded IndexedDB tree element.
Dumping IndexedDB tree:
    (empty)
Creating database.
Created database.
Refreshing.
Refreshed.
Dumping IndexedDB tree:
    database: testDatabase
        Object store: testObjectStore
            Index: testIndexName
Navigating to another security origin.
Navigated to another security origin.
Dumping IndexedDB tree:
    (empty)
Navigating back.
Navigated back.
Refreshing.
Refreshed.
Dumping IndexedDB tree:
    database: testDatabase
        Object store: testObjectStore
            Index: testIndexName
Deleting database.
Deleted database.
Refreshing.
Refreshed.
Dumping IndexedDB tree:
    (empty)