Package children can be graphically drag and dropped outside of the package west border

It is possible to do a graphical drag and drop of an element inside a package outside of its west border, as long as at least 1 pixel of the child remains in the containing package. This is not the case with the other borders (the package is either resized, or the element is moved to a location that fits inside the package).

When such a drag and drop occurs the element should be moved close to the border, inside the containing package.

Note that this only happens with Packages, other container behave as expected.