Demonstrate external-window-mode in mus-demo

services/ui/display/platform_screen_ozone.cc

Index: services/ui/display/platform_screen_ozone.cc
diff --git a/services/ui/display/platform_screen_ozone.cc b/services/ui/display/platform_screen_ozone.cc
index 5d6eea13b6cf51bb15dc4494feaad4f45fb6bddd..2004c992da766dde3de4a951bdb1a49fee3c3626 100644
--- a/services/ui/display/platform_screen_ozone.cc
+++ b/services/ui/display/platform_screen_ozone.cc
@@ -67,7 +67,8 @@ void PlatformScreenOzone::AddInterfaces(
   registry->AddInterface<mojom::TestDisplayController>(this);
 }
 
-void PlatformScreenOzone::Init(PlatformScreenDelegate* delegate) {
+void PlatformScreenOzone::Init(PlatformScreenDelegate* delegate,
+                               WindowMode window_mode) {
   DCHECK(delegate);
   delegate_ = delegate;
 
@@ -81,13 +82,15 @@ void PlatformScreenOzone::Init(PlatformScreenDelegate* delegate) {
         native_display_delegate->GetFakeDisplayController();
   }
 
-  // We want display configuration to happen even off device to keep the control
-  // flow similar.
-  display_configurator_.set_configure_display(true);
-  display_configurator_.AddObserver(this);
-  display_configurator_.set_state_controller(this);
-  display_configurator_.Init(std::move(native_display_delegate), false);
-  display_configurator_.ForceInitialConfigure(kChromeOsBootColor);
+  if (window_mode == WINDOW_MODE_INTERNAL) {
+    // We want display configuration to happen even off device to keep the
+    // control flow similar.
+    display_configurator_.set_configure_display(true);
+    display_configurator_.AddObserver(this);
+    display_configurator_.set_state_controller(this);
+    display_configurator_.Init(std::move(native_display_delegate), false);
+    display_configurator_.ForceInitialConfigure(kChromeOsBootColor);
+  }
 }
 
 void PlatformScreenOzone::RequestCloseDisplay(int64_t display_id) {