Add a contact to a group via Profile Settings "Add to Group" function removes them from any other groups that they currently belong to

hHere is one way to create it:

1. Edit name and address profile and set: add to group X
2. for your logged in contact, add to groups A, B, C
3. edit your record via profile from 1
4. save
5. go check your groups, u r in X but removed from A, B, C

Contact/BAO/Contact.php : line 270 - 274
Those lines causes havoc, since it goes in and REMOVES the contacts from the other groups they have signed into

• • • This fix should be tested for any other situation where contact can be added to group(s) AND not all groups are shown. Examples: Profile with Group(s) field included (only public groups are listed), Import might also be affected.