We need to evaluate the expression for the "with" statement that is supposed to
define the new scope _before_ opening up the scope, otherwise - when the
evaluation of the expression throws an exception - we'll try to pop the "with"
scope we couldn't open in the first place.

[ChangeLog][QtQml] Fix crash when using the "with" statement with an expression
that throws an exception.

Task-number: QTBUG-53794
Change-Id: I7733f5a4c5d844916302b9a91c789a0f6b421e8a
Reviewed-by: Lars Knoll <lars.knoll@qt.io>