33e2b82 wallet, bench: Remove unused database options from WalletBenchLoading (Andrew Chow)
80ace04 tests: Modify records directly in wallet ckey loading test (Andrew Chow)
b3bb17d tests: Update DuplicateMockDatabase for MockableDatabase (Andrew Chow)
f0eecf5 scripted-diff: Replace CreateMockWalletDB with CreateMockableWalletDB (Andrew Chow)
075962b wallet, tests: Include wallet/test/util.h (Andrew Chow)
14aa4cb wallet: Move DummyDatabase to salvage (Andrew Chow)
f67a385 wallet, tests: Replace usage of dummy db with mockable db (Andrew Chow)
33c6245 Introduce MockableDatabase for wallet unit tests (Andrew Chow)

Pull request description:

  For the wallet's unit tests, we currently use either `DummyDatabase` or memory-only versions of either BDB or SQLite. The tests that use `DummyDatabase` just need a `WalletDatabase` so that the `CWallet` can be constructed, while the tests using the memory-only databases just need a backing data store. There is also a `FailDatabase` that is similar to `DummyDatabase` except it fails be default or can have a configured return value. Having all of these different database types can make it difficult to write tests, particularly tests that work when either BDB or SQLite is disabled.

  This PR unifies all of these different unit test database classes into a single `MockableDatabase`. Like `DummyDatabase`, most functions do nothing and just return true. Like `FailDatabase`, the return value of some functions can be configured on the fly to test various failure cases. Like the memory-only databases, records can actually be written to the `MockableDatabase` and be retrieved later, but all of this is still held in memory. Using `MockableDatabase` completely removes the need for having BDB or SQLite backed wallets in the unit tests for the tests that are not actually testing specific database behaviors.

  Because `MockableDatabase`s can be created by each unit test, we can also control what records are stored in the database. Records can be added and removed externally from the typical database modification functions. This will give us greater ability to test failure conditions, particularly those involving corrupted records.

  Possible alternative to #26644

ACKs for top commit:
  furszy:
    ACK 33e2b82
  TheCharlatan:
    ACK 33e2b82

Tree-SHA512: c2b09eff9728d063d2d4aea28a0f0e64e40b76483e75dc53f08667df23bd25834d52656cd4eafb02e552db0b9e619cfdb1b1c65b26b5436ee2c971d804768bcc

69d4390 test: add coverage for wallet read write db deadlock (furszy)
12daf6f walletdb: scope bdb::EraseRecords under a single db txn (furszy)
043fcb0 wallet: bugfix, GetNewCursor() misses to provide batch ptr to BerkeleyCursor (furszy)

Pull request description:

  Decoupled from #26644 so it can closed in favor of #26715.

  Basically, with bdb, we can't make a write operation while we are traversing the db with the same db handler. These two operations are performed in different txn contexts and cause a deadlock.

  Added coverage by using `EraseRecords()` which is the simplest function that executes this process.

  To replicate it, need bdb support and drop the first commit. The test will run forever.

ACKs for top commit:
  achow101:
    ACK 69d4390
  hebasto:
    re-ACK 69d4390

Tree-SHA512: b3773be78925f674e962f4a5c54b398a9d0cfe697148c01c3ec0d68281cc5c1444b38165960d219ef3cf1a57c8ce6427f44a876275958d49bbc0808486e19d7d

69d4390 test: add coverage for wallet read write db deadlock (furszy)
12daf6f walletdb: scope bdb::EraseRecords under a single db txn (furszy)
043fcb0 wallet: bugfix, GetNewCursor() misses to provide batch ptr to BerkeleyCursor (furszy)

Pull request description:

  Decoupled from bitcoin#26644 so it can closed in favor of bitcoin#26715.

  Basically, with bdb, we can't make a write operation while we are traversing the db with the same db handler. These two operations are performed in different txn contexts and cause a deadlock.

  Added coverage by using `EraseRecords()` which is the simplest function that executes this process.

  To replicate it, need bdb support and drop the first commit. The test will run forever.

ACKs for top commit:
  achow101:
    ACK 69d4390
  hebasto:
    re-ACK 69d4390

Tree-SHA512: b3773be78925f674e962f4a5c54b398a9d0cfe697148c01c3ec0d68281cc5c1444b38165960d219ef3cf1a57c8ce6427f44a876275958d49bbc0808486e19d7d