MacViews a11y: Sync VoiceOver cursor with keyboard focus.

ui/views/cocoa/bridged_content_view.mm

Index: ui/views/cocoa/bridged_content_view.mm
diff --git a/ui/views/cocoa/bridged_content_view.mm b/ui/views/cocoa/bridged_content_view.mm
index 80243f8a5f7535b5575269562de5e452fc64613f..c267f59166f15174149828002d63e30d627e9018 100644
--- a/ui/views/cocoa/bridged_content_view.mm
+++ b/ui/views/cocoa/bridged_content_view.mm
@@ -25,6 +25,8 @@
 #include "ui/gfx/path.h"
 #import "ui/gfx/path_mac.h"
 #include "ui/gfx/scoped_ns_graphics_context_save_gstate_mac.h"
+#import "ui/accessibility/platform/ax_platform_node_mac.h"

[tapted, 2016/09/26 05:19:18]

nit: was this needed in the end?

[Patti Lor, 2016/09/28 00:29:14]

Nope, have deleted it now - thanks.

+#include "ui/views/accessibility/native_view_accessibility.h"
 #import "ui/views/cocoa/bridged_native_widget.h"
 #import "ui/views/cocoa/drag_drop_client_mac.h"
 #include "ui/views/controls/menu/menu_config.h"
@@ -1363,4 +1365,17 @@ ui::KeyEvent GetCharacterEventFromNSEvent(NSEvent* event) {
   return [hostedView_->GetNativeViewAccessible() accessibilityHitTest:point];
 }
 
+- (id)accessibilityFocusedUIElement {
+  NSWindow* keyWindow = [NSApp keyWindow];
+  // There won't be a keyWindow if there are no windows/views receiving keyboard
+  // events, which means nothing from this NSApp has focus.
+  if (!keyWindow)
+    return nil;
+
+  views::Widget* widget = views::Widget::GetWidgetForNativeWindow(keyWindow);
+  if (!widget)
+    return nil;

[tapted, 2016/09/26 05:19:17]

accessibilityFocusedUIElement says the receiver can assume that it's already
focused. widget->GetRootView() should be equivalent to |hostedView_| in that
case. But a11y requests can come in at odd times. I think this method can do

  if (!hostedView_)
    return nil;
  return hostedView_->GetNativeViewAccessibility()->GetFocus()

This ensures that we don't accidentally return a node in another window.

[Patti Lor, 2016/09/28 00:29:14]

Done.

+  return widget->GetRootView()->GetNativeViewAccessibility()->GetFocus();
+}
+
 @end