RFR: 8251862: Wrong position of Popup windows at the intersection of 2 screens [v2]

[Ambarish Rapte]

On Fri, 23 Dec 2022 14:46:25 GMT, Kevin Rushforth <kcr at openjdk.org> wrote:

>> On Windows platforms with more than one screen, a PopupWindow created for a Stage that straddles two windows will be drawn with an incorrect position and screen scale if the majority of the Stage is on one screen, and the popup is positioned on the other screen. In this case, the Stage is drawn using the screen scale of the screen that most of the window is on, while the popup is drawn using the scale of the screen that it is (typically entirely) on.
>> 
>> The most common way this can happen is when you have two screens of a different scale with the secondary screen on the left or above the primary screen. If you position the Stage such that most of it is still on the primary screen (thus the Stage is drawn using the scale of the primary screen), with a menu, a control with a context menu, or a control with a Tooltip now on the secondary screen, the popup window for the menu or Tooltip will be drawn using the screen scale of the secondary window and thus won't be positioned or sized correctly relative to the menu bar, or control in the main window.
>> 
>> The fix implemented by this PR is to always use the screen of the owner window, including the screen scales, when rendering a popup window. This matches the behavior of native Windows apps, such as Notepad.
>
> Kevin Rushforth has updated the pull request with a new target base due to a merge or a rebase. The incremental webrev excludes the unrelated changes brought in by the merge/rebase. The pull request contains two additional commits since the last revision:
> 
>  - Merge remote-tracking branch 'origin/master' into 8251862-multi-screen-popup
>  - 8251862: Wrong position of Popup windows at the intersection of 2 screens

I noticed some wrong position of menu popup when tested with 2 external monitors.
I have a monitors configured in portrait mode as:
![Screenshot 2022-12-09 145806](https://user-images.githubusercontent.com/11330676/210305749-d5073945-bfaa-44cc-98eb-172f6b344e22.png)

Screenshots of some observations:
1. 
![Screenshot 2022-12-09 144504](https://user-images.githubusercontent.com/11330676/210305790-61530649-eaec-441b-8262-ebd9f7bb877c.png)
2.
![Screenshot 2022-12-09 144624](https://user-images.githubusercontent.com/11330676/210305822-6b3aa883-bb2f-496d-9a0a-6f95fcffdddb.png)
3.
![Screenshot 2022-12-09 145645](https://user-images.githubusercontent.com/11330676/210305861-5249ee28-3898-4d5b-8b52-d3e1b3389af2.png)
4.
![Screenshot 2022-12-09 144722](https://user-images.githubusercontent.com/11330676/210305838-711ddcfa-a3ee-4b35-8b02-f1a510d080f9.png)

Similar behavior can also be observed if monitors are in landscape mode:
![Screenshot 2022-12-09 150231](https://user-images.githubusercontent.com/11330676/210305945-ba171790-4767-4cd2-96c4-2f6fb57b7e50.png)

-------------

PR: https://git.openjdk.org/jfx/pull/971