Windows/Accessibility: Qt does not report correct focused widget to screen readers on Windows

Repro steps:

1. Using any version of Qt that supports UI Automation, create a dialog with at least one child widget (see below code sample)
2. Open a screen reader such as NVDA (https://github.com/nvaccess/nvda http://nvda.bhvd.de/ ) or Narrator
3. Show the dialog
4. Observe

Expected results:

• The screen reader reads the name of the window and the focused widget (e.g. "Qt NVDA focus bug window, edit blank")
• The screen reader's focus indicator is shown around the focused widget

Actual results:

• The screen reader reads the name of the window but not the focused widget
  • NVDA reads "Qt NVDA focus bug window, edit blank, Qt NVDA focus bug window"
  • Narrator reads "Qt NVDA focus bug window"
• The screen reader's focus indicator is shown around the entire dialog contents, not the focused child widget

Additional info:

• I am upgrading an application from 5.9.3 (MSAA accessibility backend) to 5.15.1 (UIA accessibility backend).  Both NVDA and Narrator behave as expected in 5.9.3.
• I only see this issue in Qt applications.  The UIA examples on MSDN do not exhibit this issue.
• Interacting with the Qt focused widget doesn't cause the screen reader to read out the name of the focused widget.
• The same issue can be seen in the Qt "http" example (in this case, I'm using 5.12.9 because I already had that installed)

Code sample:

#include <QApplication>
#include <QHBoxLayout>
#include <QLineEdit>
#include <QPushButton>

int main(int argc, char *argv[])
{
	QApplication app(argc, argv);
	QCoreApplication::setApplicationName("Qt NVDA focus bug");

	QWidget window;
	window.resize({ 300, 100 });
	window.setLayout(new QHBoxLayout());

	QLineEdit *edit = new QLineEdit();
	window.layout()->addWidget(edit);

	QPushButton *button = new QPushButton("Browse...");
	window.layout()->addWidget(button);

	window.show();

	return app.exec();
}

See
 
https://github.com/nvaccess/nvda/blob/master/source/_UIAHandler.py : 525