- Update to 3.19.2
* Fix a bug in the LEFT JOIN flattening optimization.
Ticket cad1ab4cb7b0fc.
* Fix more bugs in the LEFT JOIN flattening optimization.
Ticket 7fde638e94287d2c.

- Update to 3.19.0
* The SQLITE_READ authorizer callback is invoked once with a
column name that is an empty string for every table referenced
in a query from which no columns are extracted.
* When using an index on an expression, try to use expression
values already available in the index, rather than loading
the original columns and recomputing the expression.
* Enhance the flattening optimization so that it is able to
flatten views on the right-hand side of a LEFT JOIN.
* Use replace() instead of char() for escaping newline and
carriage-return characters embedded in strings in the .dump
output from the command-line shell.
* Avoid unnecessary foreign key processing in UPDATE statements
that do not touch the columns that are constrained by the
foreign keys.
* On a DISTINCT query that uses an index, try to skip ahead
to the next distinct entry using the index rather than
stepping through rows, when an appropriate index is available.
* Avoid unnecessary invalidation of sqlite3_blob handles
when making changes to unrelated tables.
* Transfer any terms of the HAVING clause that use only
columns mentioned in the GROUP BY clause over to the
WHERE clause for faster processing.
* Reuse the same materialization of a VIEW if that VIEW