Update app list search box menu when Users changes

ui/app_list/views/search_box_view.cc

Index: ui/app_list/views/search_box_view.cc
diff --git a/ui/app_list/views/search_box_view.cc b/ui/app_list/views/search_box_view.cc
index ba40bf3b5f346c5bac1621c84b4ecafd3abdb9f5..bb3ae15385edafa52632e3e9ad4d8735844225e0 100644
--- a/ui/app_list/views/search_box_view.cc
+++ b/ui/app_list/views/search_box_view.cc
@@ -72,6 +72,8 @@ SearchBoxView::SearchBoxView(SearchBoxViewDelegate* delegate,
   AddChildView(search_box_);
 
   model_->search_box()->AddObserver(this);
+  view_delegate_->AddObserver(this);
+
   IconChanged();
   SpeechRecognitionButtonPropChanged();
   HintTextChanged();
@@ -79,6 +81,7 @@ SearchBoxView::SearchBoxView(SearchBoxViewDelegate* delegate,
 
 SearchBoxView::~SearchBoxView() {
   model_->search_box()->RemoveObserver(this);
+  view_delegate_->RemoveObserver(this);
 }
 
 bool SearchBoxView::HasSearch() const {
@@ -241,4 +244,8 @@ void SearchBoxView::TextChanged() {
   NotifyQueryChanged();
 }
 
+void SearchBoxView::OnUsersChanged() {
+  InvalidateMenu();
+}
+
 }  // namespace app_list