Remove icon bg color for message center notifications.

ui/message_center/notification.cc

Index: ui/message_center/notification.cc
diff --git a/ui/message_center/notification.cc b/ui/message_center/notification.cc
index b2ddd52568c491e65d2f602a4931499b9fc0e17e..2b248a006b435d256c9fe1e34f3a5240c80aaa3a 100644
--- a/ui/message_center/notification.cc
+++ b/ui/message_center/notification.cc
@@ -77,7 +77,6 @@ Notification::Notification(NotificationType type,
       title_(title),
       message_(message),
       icon_(icon),
-      draw_icon_background_(true),
       display_source_(display_source),
       origin_url_(origin_url),
       notifier_id_(notifier_id),
@@ -93,7 +92,6 @@ Notification::Notification(const std::string& id, const Notification& other)
       title_(other.title_),
       message_(other.message_),
       icon_(other.icon_),
-      draw_icon_background_(other.draw_icon_background_),
       display_source_(other.display_source_),
       origin_url_(other.origin_url_),
       notifier_id_(other.notifier_id_),
@@ -109,7 +107,6 @@ Notification::Notification(const Notification& other)
       title_(other.title_),
       message_(other.message_),
       icon_(other.icon_),
-      draw_icon_background_(other.draw_icon_background_),
       display_source_(other.display_source_),
       origin_url_(other.origin_url_),
       notifier_id_(other.notifier_id_),
@@ -125,7 +122,6 @@ Notification& Notification::operator=(const Notification& other) {
   title_ = other.title_;
   message_ = other.message_;
   icon_ = other.icon_;
-  draw_icon_background_ = other.draw_icon_background_;
   display_source_ = other.display_source_;
   origin_url_ = other.origin_url_;
   notifier_id_ = other.notifier_id_;