Removed magic

src/Gtk/Avalonia.Gtk3/PopupImpl.cs

@@ -19,24 +19,6 @@ namespace Avalonia.Gtk3
 
         public PopupImpl() : base(CreateWindow())
         {
-
-
-        }
-
-        private Size _desiredSize = new Size(1, 1);
-        public override Size ClientSize
-        {
-            get { return _desiredSize; }
-            set
-            {
-                _desiredSize = value;
-                if (GtkWidget.IsClosed)
-                    return;
-                Native.GtkWindowResize(GtkWidget, (int) value.Width, (int) value.Height);
-                if (Native.GtkWidgetGetWindow(GtkWidget) == IntPtr.Zero)
-                    Native.GtkWidgetRealize(GtkWidget);
-                Native.GdkWindowResize(Native.GtkWidgetGetWindow(GtkWidget), (int) value.Width, (int) value.Height);
-            }
         }
     }
 }

src/Gtk/Avalonia.Gtk3/TopLevelImpl.cs

@@ -46,6 +46,7 @@ namespace Avalonia.Gtk3
             ConnectEvent("key-release-event", OnKeyEvent);
             Connect<Native.D.signal_generic>("destroy", OnDestroy);
             Native.GtkWidgetRealize(gtkWidget);
+            _lastSize = ClientSize;
         }
 
         private bool OnConfigured(IntPtr gtkwidget, IntPtr ev, IntPtr userdata)
@@ -53,14 +54,14 @@ namespace Avalonia.Gtk3
             var size = ClientSize;
             if (_lastSize != size)
             {
-                _lastSize = size;
                 Resized?.Invoke(size);
+                _lastSize = size;
             }
             var pos = Position;
             if (_lastPosition != pos)
             {
-                _lastPosition = pos;
                 PositionChanged?.Invoke(pos);
+                _lastPosition = pos;
             }
 
             return false;
@@ -115,7 +116,7 @@ namespace Avalonia.Gtk3
             return true;
         }
 
-        private unsafe bool OnStateChanged(IntPtr w, IntPtr pev, IntPtr userData)
+        protected virtual unsafe bool OnStateChanged(IntPtr w, IntPtr pev, IntPtr userData)
         {
             var ev = (GdkEventWindowState*) pev;
             if (ev->changed_mask.HasFlag(GdkWindowState.Focused))
@@ -298,7 +299,7 @@ namespace Avalonia.Gtk3
         }
 
 
-        public virtual Size ClientSize
+        public Size ClientSize
         {
             get
             {