Keyboard prefs accessibility: Narrator can misread the radio buttons.

Problem. If an item in the list is selected, then if a different view by radio button is selected, Narrator reads the selected item rather than the radio button. KeyViewAx::SetCurrentLine(int line) can be called when the KeyView is not the focus, and send a focus event. Fix: In KeyViewAx::SetCurrentLine(int line), only send focus event if the KeyView is the focus.