Added an ActivationReason parameter to ActivationChangeObserver::OnWindowActivated(...).

ui/views/widget/desktop_aura/desktop_native_widget_aura.cc

Index: ui/views/widget/desktop_aura/desktop_native_widget_aura.cc
diff --git a/ui/views/widget/desktop_aura/desktop_native_widget_aura.cc b/ui/views/widget/desktop_aura/desktop_native_widget_aura.cc
index c82ced73bb74b4175c43a6b5da51e8dc80031b95..33629f9a719439469c0cf76299a1c77a35340dd8 100644
--- a/ui/views/widget/desktop_aura/desktop_native_widget_aura.cc
+++ b/ui/views/widget/desktop_aura/desktop_native_widget_aura.cc
@@ -1111,8 +1111,10 @@ bool DesktopNativeWidgetAura::ShouldActivate() const {
 // DesktopNativeWidgetAura, aura::client::ActivationChangeObserver
 //    implementation:
 
-void DesktopNativeWidgetAura::OnWindowActivated(aura::Window* gained_active,
-                                                aura::Window* lost_active) {
+void DesktopNativeWidgetAura::OnWindowActivated(
+    aura::client::ActivationChangeObserver::ActivationReason reason,
+    aura::Window* gained_active,
+    aura::Window* lost_active) {
   DCHECK(content_window_ == gained_active || content_window_ == lost_active);
   if (gained_active == content_window_ && restore_focus_on_activate_) {
     restore_focus_on_activate_ = false;