* On macOS, add `WindowBuilderExtMacOS::with_parent_window`
* Replace Parent with Option<Id<NSWindow, Shared>>
* Add addChildWindow method on NSWindow instead
* Update with_parent_window to be unsafe fn
* Add unified `with_parent_window`
* Remove `WindowBuilderExtUnix::with_parent`
* Remove `WindowBuilderExtWindows::with_parent_window`
* Clean up CI warnings
* Update CHANGELOG.md
It's `WindowBuilderExtX11` rather than `WindowBuilderExtUnix`
* Rename parent to owner
* Make with_parent_window unsafe and update its doc
* Add another way to get window on mac
* Add more documentations
* Add match arm and panic on invalid varients
* Add Xcb arm
* Update child_window example to make it safer and work in i686
* Remove duplicate entry in CHANGELOG.md
* Propogate error instead of expect
* Replace unreachable to panic
* Add platform note to X11
Co-authored-by: Wu Yu Wei <wusyong9104@gmail.com>