Subdiagrams are outside their box after autolayout and zoom

[kbirken]

From mbeddr.core created by slisson : mbeddr/mbeddr.core#1411

"This happed after I pressed the +, - and auti-layout buttons a few times.
When I click on the empty grey box, the contents suddenly jumps into it again"

[alexanderpann]

We need to check if #554 already fixes this issue.

[alexanderpann]

It is not reproducible for me with the Nested Diagram example. Seems to be fixed.