Sort icon last (#76992)

packages/flutter/lib/src/material/icon_button.dart

@@ -144,7 +144,6 @@ class IconButton extends StatelessWidget {
     this.padding = const EdgeInsets.all(8.0),
     this.alignment = Alignment.center,
     this.splashRadius,
-    required this.icon,
     this.color,
     this.focusColor,
     this.hoverColor,
@@ -158,6 +157,7 @@ class IconButton extends StatelessWidget {
     this.tooltip,
     this.enableFeedback = true,
     this.constraints,
+    required this.icon,
   }) : assert(iconSize != null),
        assert(padding != null),
        assert(alignment != null),