macviews: honor system control tint setting

ui/views/controls/button/label_button.cc

Index: ui/views/controls/button/label_button.cc
diff --git a/ui/views/controls/button/label_button.cc b/ui/views/controls/button/label_button.cc
index 860d256d0e8277bd4a0f5ef4d5d185e923241886..f8147937777dc8b575db1d55fb78e3905bafbb17 100644
--- a/ui/views/controls/button/label_button.cc
+++ b/ui/views/controls/button/label_button.cc
@@ -426,6 +426,9 @@ void LabelButton::OnNativeThemeChanged(const ui::NativeTheme* theme) {
   ResetLabelEnabledColor();
   // Invalidate the layout to pickup the new insets from the border.
   InvalidateLayout();
+  // The entire button has to be repainted here, since the native theme can
+  // define the tint for the entire background/border/focus ring.
+  SchedulePaint();
 }
 
 void LabelButton::AddInkDropLayer(ui::Layer* ink_drop_layer) {