Graceful handling and recovery for QuotaExceededError

[fl0rek]

Context

Browsers use quotas to limit the amount of data page can store locally, see mdn for details.

Available quota can be queried with StorageManager

Issue

When transaction which would put us above the quota is commited, QuotaExceededError is returned and transaction is rolled back. From this point on, Indexeddb is in read-only state until restart (note that this by itself doesn't change the quota, and db can lock up again, if quota is exceeded).

From the user perspective, node just stops syncing (as all the db inserts fail).

[zvolin]

from sync discussion:

• this is kinda similar to no space left on device error, we can't handle it really
• but we can document it
• and allow configuring the syncing window period