Fix FontSize reference (lepoco#1413)

Author: Nice3point

src/Wpf.Ui/Controls/IconElement/FontIcon.cs

@@ -110,22 +110,13 @@ public string Glyph
 
     protected TextBlock? TextBlock { get; set; }
 
-    protected override UIElement InitializeChildren()
+    public FontIcon()
     {
-        if (FontSize.Equals(SystemFonts.MessageFontSize))
-        {
-            SetResourceReference(FontSizeProperty, "DefaultIconFontSize");
-
-            // If the FontSize is the default, set it to the parent's FontSize.
-            if (
-                VisualParent is not null
-                && TextElement.GetFontSize(VisualParent) != SystemFonts.MessageFontSize
-            )
-            {
-                SetCurrentValue(FontSizeProperty, TextElement.GetFontSize(VisualParent));
-            }
-        }
+        SetCurrentValue(FontSizeProperty, UiApplication.Current.Resources["DefaultIconFontSize"]);
+    }
 
+    protected override UIElement InitializeChildren()
+    {
         TextBlock = new TextBlock
         {
             Style = null,