Impacted versions:
9.0 Community & 9.0 Enterprise

Steps to reproduce:
- Open up a V9 Enteprise Runbot
- Go to projects and open up the issues for the project 'Data Import/Export Plugin'
- Click on 'Create' to create a new issue. You will see the following form:
  ![image](https://cloud.githubusercontent.com/assets/6352350/13873556/8f826fbc-ecf2-11e5-95aa-e5cd7965b976.png)
  Notice how the Contact is filled in with the name 'Delta PC' and that no e-mail is filled in. When you open up this contact its form you will see he has an e-mail filled in:
  ![image](https://cloud.githubusercontent.com/assets/6352350/13873580/afd81f0a-ecf2-11e5-960f-91e14a999578.png)
- Remove the contact on the issue, click somewhere else and now fill in the contact again. The moment you add the contact again the onchange function goes off and the e-mail is filled in automatically:
  ![image](https://cloud.githubusercontent.com/assets/6352350/13873605/d0884068-ecf2-11e5-8892-5fcd0fc692b2.png)

Current behavior:
When clicking on 'Create' for creating a new issue on a project the customer its e-mail is not automatically filled in because the onchange does not seem to have an effect on the record.

Expected behavior:
When click on 'Create' for creating a new issue on a project the customer his e-mail is filled in automatically (provided there is one).

store={'project.issue': (lambda self, cr, uid, ids, c={}: ids, ['date_open'], 10)}),
        'working_hours_close': fields.function(_compute_day, string='Working Hours to close the Issue',
                                               multi='compute_day', type="float",
                                               store={'project.issue': (lambda self, cr, uid, ids, c={}: ids, ['date_closed'], 10)}),
        'inactivity_days': fields.function(_compute_day, string='Days since last action',
                                           multi='compute_day', type="integer", help="Difference in days between last action and current date"),
        'color': fields.integer('Color Index'),
        'user_email': fields.related('user_id', 'email', type='char', string='User Email', readonly=True),
        'date_action_last': fields.datetime('Last Action', readonly=1),
        'date_action_next': fields.datetime('Next Action', readonly=1),
        'progress': fields.function(_hours_get, string='Progress (%)', multi='hours', group_operator="avg", help="Computed as: Time Spent / Total Time.",
            store = {
                'project.issue': (lambda self, cr, uid, ids, c={}: ids, ['task_id'], 10),
                'project.task': (_get_issue_task, ['work_ids', 'remaining_hours', 'planned_hours', 'state', 'stage_id'], 10),
                'project.task.work': (_get_issue_work, ['hours'], 10),
            }),
    }
    _defaults = {
        'active': 1,
        'stage_id': lambda s, cr, uid, c: s._get_default_stage_id(cr, uid, c),
        'company_id': lambda s, cr, uid, c: s.pool.get('res.company')._company_default_get(cr, uid, 'crm.helpdesk', context=c),
        'priority': '0',
        'kanban_state': 'normal',
        'date_last_stage_update': fields.datetime.now,
        'user_id': lambda obj, cr, uid, context: uid,
    }
    _group_by_full = {
        'stage_id': _read_group_stage_ids
    }
    def copy(self, cr, uid, id, default=None, context=None):