incorrect invoice price - average price + real time missing code

to reproduce

product with
* costing method: average price
* inventory valuation: real time
* stockable

PO:
* Invoice control from picking

create some PO , process picking, validate invoice
etc

the problem
create PO , price= 10
process picking AND modify price = 11
* create stock move -
** with modified and correct price_unit = 11

* create invoice from picking
invoice line takes price from product

def _get_price_unit_invoice:
takes standard (= average) price from product

IMHO in this case the invoice should take the (modified) price from stock move.

because:
./stock.py:1213:
                        # used for inventory valuation if real-time valuation is enabled.
                        move_obj.write(cr, uid, [move.id],
                                {'price_unit': product_price,
                                 'price_currency_id': product_currency})

if the invoice is created from the picking (which is very often the case in small companies where no pricelists and standard price exists for purchased products) it does not make much sense to use/propose a different price in the invoice.

the users has to correct the price during "process picking" AND on the invoice line again. - a source of errors.