It's not enough to sanitize values when starting an animation, as the
adjustment can reconfigure itself while the animation runs.
So as a simple way to handle this, we sanitize every value right before
setting it, too.
In the future we might also want to look at sanitizing start/end values
of the animation.
Fixes #5763
{
GtkAdjustmentPrivate *priv = gtk_adjustment_get_instance_private (adjustment);
+ value = gtk_adjustment_sanitize_value (adjustment, value);
+
if (priv->value != value)
{
priv->value = value;