53e280b568
A recent change (4cb80b7ddce6f) to DBImpl::DeleteObsoleteFiles unlocked DBImpl::mutex_ while deleting files to allow for greater concurrency. This change improves on the prior in a few areas: 1. The table is evicted from the table cache before unlocking the mutex. This should only improve performance. 2. This implementation is slightly simpler, but at the cost of a bit more memory usage. 3. A comment adding more detail as to why the mutex is being unlocked and why it is safe to do so. PiperOrigin-RevId: 253111645