Do not give instant focus if a view's toplevelwidget is not active

ui/views/mus/native_widget_mus.cc

Index: ui/views/mus/native_widget_mus.cc
diff --git a/ui/views/mus/native_widget_mus.cc b/ui/views/mus/native_widget_mus.cc
index fa6641d38383c44d7ef62c29b95fb2e251788c6d..08e528d37187876e05a99afcb94cc8703dc05ee0 100644
--- a/ui/views/mus/native_widget_mus.cc
+++ b/ui/views/mus/native_widget_mus.cc
@@ -1067,11 +1067,11 @@ bool NativeWidgetMus::IsVisible() const {
 }
 
 void NativeWidgetMus::Activate() {
+  if (!window_)
+    return;
+
   static_cast<aura::client::ActivationClient*>(focus_client_.get())
       ->ActivateWindow(content_);
-  // FocusControllerMus should have focused |window_| when |content_| is
-  // activated.
-  DCHECK(!window_ || window_->HasFocus());
 }
 
 void NativeWidgetMus::Deactivate() {