Fix shelf auto-hide calculation for app-list visibility.

ash/mus/app_list_presenter_mus.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 ASH_MUS_APP_LIST_PRESENTER_MUS_H_
 #define ASH_MUS_APP_LIST_PRESENTER_MUS_H_
 
 #include "base/macros.h"
 #include "ui/app_list/presenter/app_list_presenter.h"
 #include "ui/app_list/presenter/app_list_presenter.mojom.h"
 
 namespace service_manager {
 class Connector;
 }
 
 namespace ash {
 
 // Mus+ash implementation of the AppListPresenter interface for mash, which
 // talks to the app list service in chrome.
 class AppListPresenterMus : public app_list::AppListPresenter {
  public:
   explicit AppListPresenterMus(service_manager::Connector* connector);
   ~AppListPresenterMus() override;
 
   // app_list::AppListPresenter:
   void Show(int64_t display_id) override;
   void Dismiss() override;
   void ToggleAppList(int64_t display_id) override;
-  bool IsVisible() const override;
-  bool GetTargetVisibility() const override;
+  bool IsVisible(
+      int64_t display_id = display::kInvalidDisplayId) const override;

[James Cook, 2016/11/30 23:27:19]

I don't think you're allowed to use default parameters on virtual functions.

https://google.github.io/styleguide/cppguide.html#Default_Arguments

+  bool GetTargetVisibility(
+      int64_t display_id = display::kInvalidDisplayId) const override;
 
  private:
   // Connect to the app list service in chrome if the connection hasn't
   // been established or has an error.
   void ConnectIfNeeded();
 
   service_manager::Connector* connector_;
   app_list::mojom::AppListPresenterPtr presenter_;
 
   DISALLOW_COPY_AND_ASSIGN(AppListPresenterMus);
 };
 
 }  // namespace ash
 
 #endif  // ASH_MUS_APP_LIST_PRESENTER_MUS_H_