Start to decouple display::Display from ws::PlatformDisplay.

services/ui/display/screen_manager_stub_internal.h

Index: services/ui/display/screen_manager_stub_internal.h
diff --git a/services/ui/display/screen_manager_stub_internal.h b/services/ui/display/screen_manager_stub_internal.h
index 9d278d7172e831f7a7918b39a283bc12172799f3..71645ae877e17d99a7b0c6288511fa5e443deab0 100644
--- a/services/ui/display/screen_manager_stub_internal.h
+++ b/services/ui/display/screen_manager_stub_internal.h
@@ -9,7 +9,7 @@
 
 #include "base/memory/weak_ptr.h"
 #include "services/ui/display/screen_manager.h"
-#include "services/ui/display/viewport_metrics.h"
+#include "ui/display/display.h"
 
 namespace display {
 
@@ -30,8 +30,7 @@ class ScreenManagerStubInternal : public ScreenManager {
   void RequestCloseDisplay(int64_t display_id) override;
 
   // Sample display information.
-  int64_t display_id_ = 1;
-  ViewportMetrics display_metrics_;
+  Display display_;
 
   ScreenManagerDelegate* delegate_ = nullptr;