core.expr.base: show hex attribute better in diff view

[alexanderpann]

[mgronover]

I do not understand the condition when to show the "@hex value" text within the editor (maybe to less knowlegde on my side).

Why should this work (in future)?

[alexanderpann]

There are two different editor components in the VCS language and there could be more of them in the future. That's why I only check for the package name. Very unlikely that the package name changes but this way we also avoid a dependency on the VCS plugin.