Add {Lock,Unlock,Show,Hide}Cursor() to the window manager mojom.

ash/mus/bridge/shell_port_mash.h

Index: ash/mus/bridge/shell_port_mash.h
diff --git a/ash/mus/bridge/shell_port_mash.h b/ash/mus/bridge/shell_port_mash.h
index 4d40964872ae6473e3610171d2ee6cd7b2119708..693c97ab163bd575b787005f792b58c99257bfa8 100644
--- a/ash/mus/bridge/shell_port_mash.h
+++ b/ash/mus/bridge/shell_port_mash.h
@@ -74,6 +74,9 @@ class ShellPortMash : public ShellPort, public WindowTreeHostManager::Observer {
                                 const gfx::Insets& insets) override;
   void LockCursor() override;
   void UnlockCursor() override;
+  void ShowCursor() override;
+  void HideCursor() override;
+  void SetGlobalOverrideCursor(base::Optional<ui::CursorData> cursor) override;
   bool IsMouseEventsEnabled() override;
   std::vector<WmWindow*> GetAllRootWindows() override;
   void RecordGestureAction(GestureActionType action) override;