MacViews: Fix ViewTest.HandleAccelerator by faking window activation

ui/base/test/ui_controls_mac.mm

Index: ui/base/test/ui_controls_mac.mm
diff --git a/ui/base/test/ui_controls_mac.mm b/ui/base/test/ui_controls_mac.mm
index cd4103d6db1a6827219d1297e875ece574c27608..b7615b6c2fd78eab1ddbb87a351cf33f47c4efd1 100644
--- a/ui/base/test/ui_controls_mac.mm
+++ b/ui/base/test/ui_controls_mac.mm
@@ -179,6 +179,10 @@ void EnableUIControls() {
   g_ui_controls_enabled = true;
 }
 
+bool IsUIControlsEnabled() {
+  return g_ui_controls_enabled;
+}
+
 bool SendKeyPress(gfx::NativeWindow window,
                   ui::KeyboardCode key,
                   bool control,