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
task_pool = self.pool.get('project.task')
        res = {}
        for issue in self.browse(cr, uid, ids, context=context):
            progress = 0.0
            if issue.task_id:
                progress = task_pool._hours_get(cr, uid, [issue.task_id.id], field_names, args, context=context)[issue.task_id.id]['progress']
            res[issue.id] = {'progress' : progress}
        return res
    def on_change_project(self, cr, uid, ids, project_id, context=None):
        if project_id:
            project = self.pool.get('project.project').browse(cr, uid, project_id, context=context)
            if project and project.partner_id:
                return {'value': {'partner_id': project.partner_id.id}}
        return {}
    def _get_issue_task(self, cr, uid, ids, context=None):