mus ws: Consistently use mojom::Cursor instead of int32_t.

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 0581e7e7d514a269d431349b2a82c4dd03d11bfb..027d12bfd0dcf3b8add38b1ce1f3b4aa03c211e3 100644
--- a/services/ui/ws/display.h
+++ b/services/ui/ws/display.h
@@ -145,7 +145,7 @@ class Display : public PlatformDisplayDelegate,
   // Called just before |tree| is destroyed.
   void OnWillDestroyTree(WindowTree* tree);
 
-  void UpdateNativeCursor(int32_t cursor_id);
+  void UpdateNativeCursor(mojom::Cursor cursor_id);
 
   // mojom::WindowTreeHost:
   void SetSize(const gfx::Size& size) override;
@@ -206,7 +206,7 @@ class Display : public PlatformDisplayDelegate,
   std::unique_ptr<FocusController> focus_controller_;
 
   // The last cursor set. Used to track whether we need to change the cursor.
-  int32_t last_cursor_;
+  mojom::Cursor last_cursor_;
 
   ServerWindowTracker activation_parents_;