merge layer/selection: too many conflicts created and wrong user for "their" displayed

[skyper]

I encountered this merging selection but as demo merge layer is easier and produces the same results.

What steps will reproduce the problem?

1. Have the same way in two data layer
2. modify the position of its children differently in both layers. See example Merge.joz​
3. merge layers

What is the expected result?

• Only conflict on nodes
• the user should be the same for both "my" and "their"

What happens instead?

• Conflict on way
• user on "their" is displayed from previous version and likely wrong

Please provide any additional information below. Attach a screenshot if possible.

Relative:URL: ^/trunk
Repository:UUID: 0c6e7542-c601-0410-84e7-c038aed88b3b
Last:Changed Date: 2020-03-01 01:02:24 +0100 (Sun, 01 Mar 2020)
Revision:15969
Build-Date:2020-03-01 02:30:56
URL:https://josm.openstreetmap.de/svn/trunk

[skyper]

session with two data layers

[skyper]

See #8660 for the incorrect/unneeded conflicts.