Fix up of: Don't announce 'selected' when the focus moves in Google sheets if the focused cell is the only cell selected (#8898)
* Don't announce 'selected' when the focus moves in Google sheets if the focused cell is the only cell selected.
* Address review comments.
* Address review comments.
* Update what's new
* Limit logic that stops announcing selected for a single selected item, and announces 'not selected' for not selected items, to controls that have the focusable state.
* IAccessible NVDAObject's getSelectedItemsCount_accSelection: handle a childID coming from accSelection, as found in QT tree tables like in Mumble