Add mojom::DisplayController.

services/ui/display/platform_screen_ozone.h

Index: services/ui/display/platform_screen_ozone.h
diff --git a/services/ui/display/platform_screen_ozone.h b/services/ui/display/platform_screen_ozone.h
index 0d742821830fa46584327f88db0560387470ee61..6d569e110328183926dd50f67547d59abc4423db 100644
--- a/services/ui/display/platform_screen_ozone.h
+++ b/services/ui/display/platform_screen_ozone.h
@@ -13,6 +13,7 @@
 #include "base/callback.h"
 #include "base/macros.h"
 #include "services/ui/display/platform_screen.h"
+#include "services/ui/public/interfaces/display/display_controller.mojom.h"
 #include "ui/display/chromeos/display_configurator.h"
 #include "ui/display/display.h"
 
@@ -21,7 +22,8 @@ namespace display {
 // PlatformScreenOzone provides the necessary functionality to configure all
 // attached physical displays on the ozone platform.
 class PlatformScreenOzone : public PlatformScreen,
-                            public ui::DisplayConfigurator::Observer {
+                            public ui::DisplayConfigurator::Observer,
+                            public mojom::DisplayController {
  public:
   PlatformScreenOzone();
   ~PlatformScreenOzone() override;
@@ -30,6 +32,10 @@ class PlatformScreenOzone : public PlatformScreen,
   void Init(PlatformScreenDelegate* delegate) override;
   int64_t GetPrimaryDisplayId() const override;
 
+  // mojom::DisplayController:
+  void ToggleVirtualDisplay(
+      const ToggleVirtualDisplayCallback& callback) override;
+
  private:
   // TODO(kylechar): This struct is just temporary until we migrate
   // DisplayManager code out of ash so it can be used here.