[Workspaces] Wrong layering after moving windows across workspaces

[mpanasyuk]

Active window is covered by an inactive one.

How to reproduce:

1) Open 2 windows. Open Workspaces app.

2) Bring one window to foreground and move it to another workspace without switching to it.

3) Bring second window to foreground.

4) Move first window from another workspace again without switching workspaces.

5) Select second window - it is selected (tab is yellow) but not foreground, first window is over it.

[mmadia]

duplicate of #4662.