[XembedSNIProxy] Redirect and handle structure requests on the embedded window.

Summary:
When the window is embedded, it should not request position change. Sometimes applications are misbehaving and ignore this constrain. We need to capture all structure requests (position or size change) and ignore them. In other words, we must be a window manager for the embedded window.

BUG: 414667

Test Plan:
0. You need multiples screens to test this

1. Configure screens so that (0,0) is not on the primary screen
2. Run any Windows app with tray icon using Wine
3. Left click event should work correctly

Reviewers: Plasma: Workspaces, Plasma, davidedmundson

Reviewed By: Plasma: Workspaces, Plasma, davidedmundson

Subscribers: plasma-devel

Tags: Plasma

Differential Revision: https://phabricator.kde.org/D26079