**Impacted versions:** 8.0

**Steps to reproduce:**
To reproduce it is necessary the fifo configuration in the assignation of quants in moves.

- Create a sale order with two lines of the same product, one of that line with a route that generate moves between warehouse.

<img width="1231" alt="skitch 65" src="https://cloud.githubusercontent.com/assets/11341058/24102907/d575a638-0d53-11e7-922e-a3f034d43e94.png">

The route used has three pull rules:

1. From Stock Warehouse_1 to Virtual Locations/Inter Company Transit
2. From Virtual Locations/Inter Company Transit to Stock Warehouse_2
3. From Stock Warehouse_2 to Customers

<img width="1224" alt="skitch 66" src="https://cloud.githubusercontent.com/assets/11341058/24103147/b7c2bfbc-0d54-11e7-955c-87247a10e0bd.png">

- Confirm the sale order. It must be created three pickings:

<img width="1226" alt="skitch 67" src="https://cloud.githubusercontent.com/assets/11341058/24103498/d90c9b38-0d55-11e7-97ff-f986df8cdd9b.png">

- Transfer first two pickings.

<img width="1230" alt="skitch 70" src="https://cloud.githubusercontent.com/assets/11341058/24104496/b7b0be8a-0d58-11e7-89a2-4331fceec1d8.png">

- Before transfer third picking, review that one move has reserved the quant correctly because was reserved from the previous pickings.

<img width="1215" alt="skitch 68" src="https://cloud.githubusercontent.com/assets/11341058/24103908/23952cc8-0d57-11e7-9346-bd48d7edb54a.png">

**Current behavior:**

When check availability of this third picking, the quant already reserved is moved to the other move.

<img width="1264" alt="skitch 69" src="https://cloud.githubusercontent.com/assets/11341058/24104056/8be11616-0d57-11e7-8763-a90507315b19.png">
 
**Expected behavior:**

When check availability of this third picking, the moves already reserved must not be altered.


addons/stock/stock.py
('confirmed', 'Waiting Availability'),
                ('partially_available', 'Partially Available'),
                ('assigned', 'Ready to Transfer'),
                ('done', 'Transferred'),
                ], string='Status', readonly=True, select=True, track_visibility='onchange',
            help="""
                * Draft: not confirmed yet and will not be scheduled until confirmed\n
                * Waiting Another Operation: waiting for another move to proceed before it becomes automatically available (e.g. in Make-To-Order flows)\n
                * Waiting Availability: still waiting for the availability of products\n
                * Partially Available: some products are available and reserved\n
                * Ready to Transfer: products reserved, simply waiting for confirmation.\n
                * Transferred: has been processed, can't be modified or cancelled anymore\n
                * Cancelled: has been cancelled, can't be confirmed anymore"""
        ),
        'priority': fields.function(get_min_max_date, multi="min_max_date", fnct_inv=_set_priority, type='selection', selection=procurement.PROCUREMENT_PRIORITIES, string='Priority',
                                    store={'stock.move': (_get_pickings_dates_priority, ['priority', 'picking_id'], 20)}, states={'done': [('readonly', True)], 'cancel': [('readonly', True)]}, select=1, help="Priority for this picking. Setting manually a value here would set it as priority for all the moves",
                                    track_visibility='onchange', required=True),
        'min_date': fields.function(get_min_max_date, multi="min_max_date", fnct_inv=_set_min_date,
                 store={'stock.move': (_get_pickings_dates_priority, ['date_expected', 'picking_id'], 20)}, type='datetime', states={'done': [('readonly', True)], 'cancel': [('readonly', True)]}, string='Scheduled Date', select=1, help="Scheduled time for the first part of the shipment to be processed. Setting manually a value here would set it as expected date for all the stock moves.", track_visibility='onchange'),
        'max_date': fields.function(get_min_max_date, multi="min_max_date",
                 store={'stock.move': (_get_pickings_dates_priority, ['date_expected', 'picking_id'], 20)}, type='datetime', string='Max. Expected Date', select=2, help="Scheduled time for the last part of the shipment to be processed"),
        'date': fields.datetime('Creation Date', help="Creation Date, usually the time of the order", select=True, states={'done': [('readonly', True)], 'cancel': [('readonly', True)]}, track_visibility='onchange'),
        'date_done': fields.datetime('Date of Transfer', help="Date of Completion", states={'done': [('readonly', True)], 'cancel': [('readonly', True)]}, copy=False),
        'move_lines': fields.one2many('stock.move', 'picking_id', 'Internal Moves', states={'done': [('readonly', True)], 'cancel': [('readonly', True)]}, copy=True),
        'quant_reserved_exist': fields.function(_get_quant_reserved_exist, type='boolean', string='Quant already reserved ?', help='technical field used to know if there is already at least one quant reserved on moves of a given picking'),
        'partner_id': fields.many2one('res.partner', 'Partner', states={'done': [('readonly', True)], 'cancel': [('readonly', True)]}),
        'company_id': fields.many2one('res.company', 'Company', required=True, select=True, states={'done': [('readonly', True)], 'cancel': [('readonly', True)]}),
        'pack_operation_ids': fields.one2many('stock.pack.operation', 'picking_id', states={'done': [('readonly', True)], 'cancel': [('readonly', True)]}, string='Related Packing Operations'),
        'pack_operation_exist': fields.function(_get_pack_operation_exist, type='boolean', string='Pack Operation Exists?', help='technical field for attrs in view'),
        'picking_type_id': fields.many2one('stock.picking.type', 'Picking Type', states={'done': [('readonly', True)], 'cancel': [('readonly', True)]}, required=True),