[WIP] Move ownership of PlatformDisplay from ws::Display to ws::WindowServer

services/ui/ws/display.h

Index: services/ui/ws/display.h
diff --git a/services/ui/ws/display.h b/services/ui/ws/display.h
index 679a338fab81a596d4d1ccd6e1576c685c2ea6aa..c3ce55ea338a7b0649364002f653b3d6ed6e7b44 100644
--- a/services/ui/ws/display.h
+++ b/services/ui/ws/display.h
@@ -72,7 +72,7 @@ class Display : public PlatformDisplayDelegate,
   DisplayManager* display_manager();
   const DisplayManager* display_manager() const;
 
-  PlatformDisplay* platform_display() { return platform_display_.get(); }
+  PlatformDisplay* platform_display() { return platform_display_; }
 
   // Returns a display::Display corresponding to this ws::Display.
   display::Display ToDisplay() const;
@@ -194,7 +194,7 @@ class Display : public PlatformDisplayDelegate,
   std::unique_ptr<DisplayBinding> binding_;
   WindowServer* const window_server_;
   std::unique_ptr<ServerWindow> root_;
-  std::unique_ptr<PlatformDisplay> platform_display_;
+  PlatformDisplay* platform_display_;
   std::unique_ptr<FocusController> focus_controller_;
 
   // The last cursor set. Used to track whether we need to change the cursor.