0030493: Shipment Negative Lines appear in Pick/Edit Lines grid in Return From Customer when they should not

Description

Shipment Negative Lines appear in Pick/Edit Lines grid in Return From Customer when they should not. It makes no sense to return a negative shipment, because in the end a negative shipment is a return so what would be that? a normal shipment? Makes no sense.
At least the validation existing in the grid it does not allow to select the negative line and set any quantity, so it will never be created a return line against that negative shipment. But it should not appear in the grid because it is confusing.

Steps To Reproduce

As F&B Group Admin:
* Go to Sales Order window and create a Sales Order with a product with stock for quantity -5.
* Go to Create Shipments from Orders and create the shipment from the previous Sales Order.
* Go to Return from Customer Window and create a header for the same Business Partner as previous Order/Shipment.
* Click on Pick&Edit Lines and check that the previous shipment line appears. Set any quantity on Returned field. Always an error is obtained.

Issue History
Date Modified	Username	Field	Change
2015-08-04 11:31	umartirena	New Issue
2015-08-04 11:31	umartirena	Assigned To	=> Triage Finance
2015-08-04 11:31	umartirena	Modules	=> Core
2015-08-04 11:31	umartirena	Triggers an Emergency Pack	=> No

Relationships [ Relation Graph ] [ Dependency Graph ]

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