Add a policy to always show the Cast toolbar icon

chrome/browser/ui/toolbar/media_router_contextual_menu.h

 // Copyright 2015 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.
 
 #ifndef CHROME_BROWSER_UI_TOOLBAR_MEDIA_ROUTER_CONTEXTUAL_MENU_H_
 #define CHROME_BROWSER_UI_TOOLBAR_MEDIA_ROUTER_CONTEXTUAL_MENU_H_
 
 #include "base/macros.h"
 #include "base/strings/utf_string_conversions.h"
 #include "ui/base/models/simple_menu_model.h"
 
 class Browser;
 
 namespace extensions {
 class ComponentMigrationHelper;
 }  // namespace extensions
 
 // The class for the contextual menu for the Media Router action.
 class MediaRouterContextualMenu : public ui::SimpleMenuModel::Delegate {
  public:
   explicit MediaRouterContextualMenu(Browser* browser);
+
+  // Constructor for injecting values in tests.
+  MediaRouterContextualMenu(Browser* browser, bool shown_by_policy);

[msw, 2017/01/05 01:14:57]

Can the test mark the preference as managed (policy-defined) instead?

[takumif, 2017/01/06 22:06:57]

That'd require moving the test to MediaRouterActionEnabledPolicyTest in
policy_browsertest.cc, and setting up there would be more difficult.

[msw, 2017/01/06 23:01:23]

Hmm, okay; this ctor flag seems fine to use a unit test over a browser test.

   ~MediaRouterContextualMenu() override;
 
   ui::MenuModel* menu_model() { return &menu_model_; }
 
  private:
   FRIEND_TEST_ALL_PREFIXES(MediaRouterContextualMenuUnitTest,
                            ToggleCloudServicesItem);
   FRIEND_TEST_ALL_PREFIXES(MediaRouterContextualMenuUnitTest,
                            ToggleAlwaysShowIconItem);
+  FRIEND_TEST_ALL_PREFIXES(MediaRouterContextualMenuUnitTest,
+                           ActionShownByPolicy);
 
   // Gets or sets the "Always show icon" option.
   bool GetAlwaysShowActionPref() const;
   void SetAlwaysShowActionPref(bool always_show);
 
   // ui::SimpleMenuModel::Delegate:
   bool IsCommandIdChecked(int command_id) const override;
   bool IsCommandIdEnabled(int command_id) const override;
   bool IsCommandIdVisible(int command_id) const override;
   void ExecuteCommand(int command_id, int event_flags) override;
 
   void ReportIssue();
 
   Browser* const browser_;
   ui::SimpleMenuModel menu_model_;
   extensions::ComponentMigrationHelper* const component_migration_helper_;
 
+  // Whether the media router action is shown by an administrator policy.
+  bool shown_by_policy_;
+
   DISALLOW_COPY_AND_ASSIGN(MediaRouterContextualMenu);
 };
 
 #endif  // CHROME_BROWSER_UI_TOOLBAR_MEDIA_ROUTER_CONTEXTUAL_MENU_H_