Ensure that new toolbar actions added to incognito toolbars become visible

chrome/browser/ui/toolbar/toolbar_actions_model.cc

 // Copyright (c) 2012 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #include "chrome/browser/ui/toolbar/toolbar_actions_model.h"
 
 #include <algorithm>
 #include <string>
 
 #include "base/location.h"
@@ skipping 370 matching lines @@
       visible_count_delta = 1;
     } else if (profile_->IsOffTheRecord()) {
       // If this is an incognito profile, we also have to check to make sure the
       // overflow matches the main bar's status.
       ToolbarActionsModel* main_model =
           ToolbarActionsModel::Get(profile_->GetOriginalProfile());
       // Find what the index will be in the main bar. Because Observer calls are
       // 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.
       if (visible && !all_icons_visible())
         visible_count_delta = 1;
       else if (!visible && all_icons_visible())
         visible_count_delta = -1;
     }
 
     if (visible_count_delta)
@@ skipping 457 matching lines @@
   return extension_registry_->enabled_extensions().GetByID(id);
 }
 
 bool ToolbarActionsModel::IsActionVisible(const std::string& action_id) const {
   size_t index = 0u;
   while (toolbar_items().size() > index &&
          toolbar_items()[index].id != action_id)
     ++index;
   return index < visible_icon_count();
 }