[Windows] Run/Close Content while the taskbar is on top and not hidden causes Retroarch to migrate up the screen

Description

This one is kind of weird. When performing any action that causes the window to close and reopen (Run Content, Close Content, etc.) AND the taskbar location is set to "top" without hiding, Retroarch reappears ~50 pixels higher instead of in the same place. When the taskbar is in any other position (left, right, bottom) or when it is on the top but hidden, Retroarch reappears in the correct position. It's only when the taskbar is on the top and not hidden that this occurs.

Expected behavior

I expect the window to disappear and reappear in the same place, as so:

https://user-images.githubusercontent.com/12647331/108789006-4d017100-7547-11eb-9377-940ce10d1f31.mp4

Actual behavior

Instead, the window reappears a little higher on the monitor, eventually putting itself under the taskbar or off the top of the screen. Here's an example:

https://user-images.githubusercontent.com/12647331/108788571-43c3d480-7546-11eb-8133-910f15941710.mp4

Steps to reproduce the bug

1. Move your taskbar to the top of your monitor, either by dragging or through the taskbar settings.
2. In your taskbar settings, ensure "Automatically hide taskbar in desktop mode" is unchecked.
3. Open Retroarch and select a game.
4. Starting or closing out of a game should cause the described bug.

Bisect Results

I've had this issue for years, and I'm not aware of a time I haven't experienced this bug. I only brought it forward now because I realized it might be a Retroarch problem and not a Windows problem (though it might be that).

Version/Commit

You can find this information under Information/System Information

• RetroArch: version 5e551dd92b

Environment information

• OS: Windows 10 build 19042

Reproduce the issue on Windows 10 with the taskbar positioned at the top and not hidden, then compare the window position before and after Run Content or Close Content. Trace the close-and-reopen window positioning path and verify that the window returns to the same location without moving under or off the taskbar.