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).

addons/project_issue/project_issue.py
""" Overrides mail_thread message_new that is called by the mailgateway
            through message_process.
            This override updates the document according to the email.
        """
        if custom_values is None:
            custom_values = {}
        context = dict(context or {}, state_to='draft')
        defaults = {
            'name':  msg.get('subject') or _("No Subject"),
            'email_from': msg.get('from'),
            'email_cc': msg.get('cc'),
            'partner_id': msg.get('author_id', False),
            'user_id': False,
        }
        defaults.update(custom_values)
        res_id = super(project_issue, self).message_new(cr, uid, msg, custom_values=defaults, context=context)
        return res_id
    @api.cr_uid_ids_context
    def message_post(self, cr, uid, thread_id, body='', subject=None, type='notification', subtype=None, parent_id=False, attachments=None, context=None, content_subtype='html', **kwargs):
        """ Overrides mail_thread message_post so that we can set the date of last action field when
            a new message is posted on the issue.
        """
        if context is None:
            context = {}
        res = super(project_issue, self).message_post(cr, uid, thread_id, body=body, subject=subject, type=type, subtype=subtype, parent_id=parent_id, attachments=attachments, context=context, content_subtype=content_subtype, **kwargs)
        if thread_id and subtype:
            self.write(cr, SUPERUSER_ID, thread_id, {'date_action_last': fields.datetime.now()}, context=context)
        return res
class project(osv.Model):