Change Painter factory functions to unique_ptr

ui/views/controls/button/label_button_border.cc

Index: ui/views/controls/button/label_button_border.cc
diff --git a/ui/views/controls/button/label_button_border.cc b/ui/views/controls/button/label_button_border.cc
index bf8b584272fa6e604d50eba0732da7af4e19c82b..b1ff3a56206352f4f20119941312ef841c2ffc04 100644
--- a/ui/views/controls/button/label_button_border.cc
+++ b/ui/views/controls/button/label_button_border.cc
@@ -183,8 +183,8 @@ Painter* LabelButtonAssetBorder::GetPainter(bool focused,
 
 void LabelButtonAssetBorder::SetPainter(bool focused,
                                         Button::ButtonState state,
-                                        Painter* painter) {
-  painters_[focused ? 1 : 0][state].reset(painter);
+                                        std::unique_ptr<Painter> painter) {
+  painters_[focused ? 1 : 0][state] = std::move(painter);
 }
 
 }  // namespace views