WindowServer: Move child windows together with their parents

When moving a window, we will now move any child windows by the same
position delta as the parent. This makes ComboBox popup list windows
follow the window they were opened by, which looks nice. :^)

1 files changed, 3 insertions, 9 deletions

diff --git a/Servers/WindowServer/Window.h b/Servers/WindowServer/Window.h
index 71e8d6bfc0..5705d09114 100644
--- a/Servers/WindowServer/Window.h
+++ b/Servers/WindowServer/Window.h
@@ -142,15 +142,7 @@ public:
     Gfx::Rect rect() const { return m_rect; }
     void set_rect(const Gfx::Rect&);
     void set_rect(int x, int y, int width, int height) { set_rect({ x, y, width, height }); }
-    void set_rect_without_repaint(const Gfx::Rect& rect)
-    {
-        ASSERT(!rect.is_empty());
-        if (m_rect == rect)
-            return;
-        auto old_rect = m_rect;
-        m_rect = rect;
-        m_frame.notify_window_rect_changed(old_rect, rect);
-    }
+    void set_rect_without_repaint(const Gfx::Rect&);
 
     void set_taskbar_rect(const Gfx::Rect& rect) { m_taskbar_rect = rect; }
     const Gfx::Rect& taskbar_rect() const { return m_taskbar_rect; }
@@ -158,6 +150,8 @@ public:
     void move_to(const Gfx::Point& position) { set_rect({ position, size() }); }
     void move_to(int x, int y) { move_to({ x, y }); }
 
+    void move_by(const Gfx::Point& delta) { set_position_without_repaint(position().translated(delta)); }
+
     Gfx::Point position() const { return m_rect.location(); }
     void set_position(const Gfx::Point& position) { set_rect({ position.x(), position.y(), width(), height() }); }
     void set_position_without_repaint(const Gfx::Point& position) { set_rect_without_repaint({ position.x(), position.y(), width(), height() }); }