Description:
------------
If SQLite3Stmt::bindValue() is called with the explicit $type
SQLITE3_FLOAT, and a $value which is not a float, garbage is
written to the database in the best case.

For some reason the respective conversion to double[1] is
commented out since ext/sqlite3 has been moved to php-src (and
actually has been commented out at least since PECL/sqlite3
version 0.3).

[1] <https://github.com/php/php-src/blob/php-7.2.8/ext/sqlite3/sqlite3.c#L1598>


Test script:
---------------
<?php
$db = new SQLite3('memory');
$db->exec("CREATE TABLE foo (bar REAL)");
$stmt = $db->prepare("INSERT INTO foo VALUES (:bar)");
$stmt->bindValue(':bar', 17, SQLITE3_FLOAT);
$stmt->execute();
var_dump($db->querySingle("SELECT bar FROM foo LIMIT 1"));


Expected result:
----------------
float(17)

Actual result:
--------------
float(8.3991159793012E-323)