Create MediaRouterActionController and MediaRouterUIService

chrome/browser/ui/toolbar/media_router_action_controller.h

+// Copyright 2016 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_ACTION_CONTROLLER_H_
+#define CHROME_BROWSER_UI_TOOLBAR_MEDIA_ROUTER_ACTION_CONTROLLER_H_
+
+#include <memory>
+#include <string>
+#include <vector>
+
+#include "chrome/browser/extensions/component_migration_helper.h"
+#include "chrome/browser/media/router/issues_observer.h"
+#include "chrome/browser/media/router/media_routes_observer.h"
+#include "chrome/browser/profiles/profile.h"
+#include "components/prefs/pref_change_registrar.h"
+
+using extensions::ComponentMigrationHelper;
+
+class Profile;
+
+// Controller for MediaRouterAction that determines when to show and hide the
+// action icon on the toolbar. There should be one instance of this class per
+// profile, and it should only be used on the UI thread.
+class MediaRouterActionController : public media_router::IssuesObserver,
+                                    public media_router::MediaRoutesObserver {
+ public:
+  explicit MediaRouterActionController(Profile* profile);
+  // Constructor for injecting dependencies in tests.

[imcheng, 2016/09/13 23:13:10]

nit: blank line before comment

[takumif, 2016/09/14 04:00:52]

Moving the ctor to private.

+  MediaRouterActionController(

[imcheng, 2016/09/13 23:13:10]

nit: consider moving this ctor to private and adding the test class as friends.

[takumif, 2016/09/14 04:00:52]

Done.

+      Profile* profile,
+      media_router::MediaRouter* router,
+      ComponentMigrationHelper::ComponentActionDelegate*
+          component_action_delegate,
+      ComponentMigrationHelper* component_migration_helper);
+  ~MediaRouterActionController() override;
+
+  // media_router::IssuesObserver:
+  void OnIssueUpdated(const media_router::Issue* issue) override;
+
+  // media_router::MediaRoutesObserver:
+  void OnRoutesUpdated(const std::vector<media_router::MediaRoute>& routes,
+                       const std::vector<media_router::MediaRoute::Id>&
+                           joinable_route_ids) override;
+
+ private:
+  FRIEND_TEST_ALL_PREFIXES(MediaRouterActionControllerUnitTest, EphemeralIcon);
+
+  // Adds or removes the Media Router action icon to/from
+  // |component_action_delegate_| if necessary, depending on whether or not
+  // we have issues or local routes.
+  void MaybeAddOrRemoveAction();
+
+  // Returns ture if the Media Router action should be present on the toolbar

[imcheng, 2016/09/13 23:13:10]

s/ture/|true|

[takumif, 2016/09/14 04:00:52]

Oops. Replaced.

+  // or the overflow menu.
+  bool IsActionEnabled();

[imcheng, 2016/09/13 23:13:10]

const

[takumif, 2016/09/14 04:00:52]

Done.

+
+  // The profile |this| is associated with. There should be one instance of this
+  // class per profile.
+  Profile* const profile_;
+
+  // The delegate that is responsible for showing and hiding the icon on the
+  // toolbar. It is a KeyedService and outlives |this|.
+  ComponentMigrationHelper::ComponentActionDelegate* const
+      component_action_delegate_;
+
+  // Responsible for changing the pref to always show or hide component actions.
+  // It is owned by ToolbarActionsModel and outlives |this|.
+  ComponentMigrationHelper* const component_migration_helper_;
+
+  bool has_issue_;
+  bool has_local_display_route_;
+
+  PrefChangeRegistrar pref_change_registrar_;
+
+  DISALLOW_COPY_AND_ASSIGN(MediaRouterActionController);
+};
+
+#endif  // CHROME_BROWSER_UI_TOOLBAR_MEDIA_ROUTER_ACTION_CONTROLLER_H_