Editing a person to add tag will remove the displaying of existing event assigned to the person

[brianchoon]

Suppose we start with the below address book for persons:

Observe that Amy is assigned to the event Graduation.

Now, I attempt to assign a tag to Amy, by typing this in:

Notice that the Graduation word is now gone, replaced by sister:

A fix for this bug would be to ensure that we display both person tags and the events that a person is assigned to.