Show the Cast toolbar icon ephemerally when Cast is in use

chrome/browser/ui/toolbar/toolbar_actions_bar.cc

 // Copyright 2014 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_bar.h"
 
 #include <utility>
 
 #include "base/auto_reset.h"
 #include "base/location.h"
@@ skipping 660 matching lines @@
   toolbar_actions_.weak_erase(iter);
   delegate_->RemoveViewForAction(removed_action.get());
   if (popped_out_action_ == removed_action.get())
     UndoPopOut();
   removed_action.reset();
 
   // If the extension is being upgraded we don't want the bar to shrink
   // because the icon is just going to get re-added to the same location.
   // There is an exception if this is an off-the-record profile, and the
   // extension is no longer incognito-enabled.
-  if (!extensions::ExtensionSystem::Get(browser_->profile())
-           ->runtime_data()
-           ->IsBeingUpgraded(action_id) ||
+  if (ComponentToolbarActionsFactory::GetInstance()
+          ->IsComponentActionId(action_id) ||
+      !extensions::ExtensionSystem::Get(browser_->profile())
+          ->runtime_data()
+          ->IsBeingUpgraded(action_id) ||
       (browser_->profile()->IsOffTheRecord() &&
        !extensions::util::IsIncognitoEnabled(action_id, browser_->profile()))) {
     if (toolbar_actions_.size() > model_->visible_icon_count()) {
       // If we have more icons than we can show, then we must not be changing
       // the container size (since we either removed an icon from the main
       // area and one from the overflow list will have shifted in, or we
       // removed an entry directly from the overflow list).
       delegate_->Redraw(false);
     } else {
       // Either we went from overflow to no-overflow, or we shrunk the no-
@@ skipping 130 matching lines @@
   for (ToolbarActionViewController* action : toolbar_actions_) {
     if (action->GetId() == action_id)
       return action;
   }
   return nullptr;
 }
 
 content::WebContents* ToolbarActionsBar::GetCurrentWebContents() {
   return browser_->tab_strip_model()->GetActiveWebContents();
 }