Enable the new dialog style by default; etc.

ui/views/controls/button/label_button.h

Index: ui/views/controls/button/label_button.h
diff --git a/ui/views/controls/button/label_button.h b/ui/views/controls/button/label_button.h
index b96c7854de60267627dded24aee36ae42f83620f..38417672e63aafba6973f6964057e11edd380b27 100644
--- a/ui/views/controls/button/label_button.h
+++ b/ui/views/controls/button/label_button.h
@@ -114,6 +114,9 @@ class VIEWS_EXPORT LabelButton : public CustomButton,
   // |max_size_| may be set to clamp the preferred size.
   gfx::Size max_size_;
 
+  // A cached preferred size; used to avoid costly text size calculations.
+  gfx::Size cached_size_;
+
   // Flag indicating default handling of the return key via an accelerator.
   // Whether or not the button appears or behaves as the default button in its
   // current context;