mus: Implement Window Server Capture

components/mus/public/cpp/lib/window_tree_client_impl.h

Index: components/mus/public/cpp/lib/window_tree_client_impl.h
diff --git a/components/mus/public/cpp/lib/window_tree_client_impl.h b/components/mus/public/cpp/lib/window_tree_client_impl.h
index 4d86feff6f10c506369fb17f68fda5da74a3bbd7..a7b6a93fb1c6aec745c915d89c464f5d0d7965d1 100644
--- a/components/mus/public/cpp/lib/window_tree_client_impl.h
+++ b/components/mus/public/cpp/lib/window_tree_client_impl.h
@@ -73,6 +73,8 @@ class WindowTreeClientImpl : public WindowTreeConnection,
   void SetBounds(Window* window,
                  const gfx::Rect& old_bounds,
                  const gfx::Rect& bounds);
+  void SetCapture(Window* window);
+  void ReleaseCapture(Window* window);
   void SetClientArea(Id window_id,
                      const gfx::Insets& client_area,
                      const std::vector<gfx::Rect>& additional_client_areas);
@@ -171,6 +173,7 @@ class WindowTreeClientImpl : public WindowTreeConnection,
                uint32_t access_policy) override;
   void OnEmbeddedAppDisconnected(Id window_id) override;
   void OnUnembed(Id window_id) override;
+  void OnLostCapture(Id window_id) override;
   void OnTopLevelCreated(uint32_t change_id,
                          mojom::WindowDataPtr data) override;
   void OnWindowBoundsChanged(Id window_id,