Remove some temporary code in mallocA.test that was accidentally checked in.
Ensure that the Pager.pTmpSpace allocation is correct even if an OOM error
occurs while reducing the page size.
Set the connection-specific lastRowid value before calling any SQL function.
Fix up test cases to account for the new SQLITE_LIMIT_WORKER_THREADS limit.
Remove an always-true branch in whereRangeScanEst().  Replace it with an
assert().