tasks = fields.One2Many(
        'quality.task', 'origin', "Tasks", readonly=True)
    quality_tasks = fields.One2Many(
        'quality.task', 'origin', "Quality Tasks", readonly=True,
        filter=[
            ('task_type', '=', 'quality'),
            ])
....

OR
....
    tasks = fields.One2Many(
        'quality.task', 'origin', "Tasks", readonly=True)
    quality_tasks = fields.Function(
        fields.One2Many('quality.task', 'origin', "Quality Tasks Quality", readonly=True),
        'get_quality_tasks')

    def get_quality_tasks(self, name):
        return [t.id for t in tasks if t.task_type == 'quality']
....