Ensure that new toolbar actions added to incognito toolbars become visible

chrome/browser/ui/toolbar/toolbar_actions_model.cc

Index: chrome/browser/ui/toolbar/toolbar_actions_model.cc
diff --git a/chrome/browser/ui/toolbar/toolbar_actions_model.cc b/chrome/browser/ui/toolbar/toolbar_actions_model.cc
index 25cc67103e1a4dae1a07e2308ee3c59d608501d1..0f9a51bf4ebed0b832a53d7791ad7b0a5494ab7b 100644
--- a/chrome/browser/ui/toolbar/toolbar_actions_model.cc
+++ b/chrome/browser/ui/toolbar/toolbar_actions_model.cc
@@ -388,7 +388,8 @@ void ToolbarActionsModel::AddItem(const ToolbarItem& item) {
       // nondeterministic, we can't just assume the main bar will have the
       // extension and look it up.
       size_t main_index = main_model->FindNewPositionFromLastKnownGood(item);
-      bool visible = main_index < main_model->visible_icon_count();
+      bool visible =
+          is_new_extension || main_index < main_model->visible_icon_count();
       // We may need to adjust the visible count if the incognito bar isn't
       // showing all icons and this one is visible, or if it is showing all
       // icons and this is hidden.