res.users form contains virtual fields in_group_ID to be added in res.groups.
Groups with boolean share=True (added by share module) must not be displayed in
the form and should not be modifiable through the user interface.
However, if a module adding/modifying a res.group is earlier in the dependency
graph than 'share' (e.g. only depends from 'base'), the update of the user view
is done before share is loaded and the overrride of 'get_application_groups' is
never executed.
As we can not guarantee that the module is share loaded, put the logic of
hidding the module in base instead of share.
This workaround is quite hacky but is necessary in stable version.
Better fix in 9.0 at cf63d4d
Fixes#6324Fixes#5820