[FIX] mrp: BOM state button from product.product

When clicking on the BOM state button from product.product, and clicking
on create afterward, it must open mrp.bom view with the product and product variant
already set(as with product.template).

opw:645045

addons/mrp/product.py

@@ -92,7 +92,7 @@ class product_product(osv.osv):
                     ('product_id', '=', False),
                     ('product_tmpl_id', 'in', list(products)),
         ]
-        result['context'] = "{}"
+        result['context'] = "{'default_product_id': active_id, 'search_default_product_id': active_id, 'default_product_tmpl_id': %s}" % (len(products) and products.pop() or 'False')
         result['domain'] = str(domain)
         return result