async function deleteDatabase() {
    const idbFactory = getIndexedDBFactory();
    return new Promise((resolve, reject)=>{
        const deleteRequest = idbFactory.deleteDatabase(DATABASE_NAME);
        deleteRequest.onsuccess = ()=>resolve();
        deleteRequest.onerror = (error)=>reject(error);
    });
}
Creates a browser IndexedDB IOHandler for saving and loading models.

```js
const model = tf.sequential();
model.add(
    tf.layers.dense({units: 1, inputShape: [100], activation: 'sigmoid'}));

const saveResult = await model.save('indexeddb://MyModel'));
console.log(saveResult);
```

@param modelPath A unique identifier for the model to be saved. Must be a
  non-empty string.
@returns An instance of `BrowserIndexedDB` (sublcass of `IOHandler`),
  which can be used with, e.g., `tf.Model.save`.