mash: Migrate shelf app list button to wm common types

ash/common/wm_shell.h

Index: ash/common/wm_shell.h
diff --git a/ash/common/wm_shell.h b/ash/common/wm_shell.h
index 3ae326554ffedc20e7cbc51e393428051bd4781a..71e7480ffae5f9ce3e00d50341975c1139116f3c 100644
--- a/ash/common/wm_shell.h
+++ b/ash/common/wm_shell.h
@@ -31,6 +31,7 @@ class MaximizeModeController;
 class MruWindowTracker;
 class ScopedDisableInternalMouseAndKeyboard;
 class SessionStateDelegate;
+class ShelfModel;
 class ShellDelegate;
 class ShellObserver;
 class SystemTrayDelegate;
@@ -92,6 +93,8 @@ class ASH_EXPORT WmShell {
 
   MediaDelegate* media_delegate() { return media_delegate_.get(); }
 
+  ShelfModel* shelf_model() { return shelf_model_.get(); }
+
   SystemTrayNotifier* system_tray_notifier() {
     return system_tray_notifier_.get();
   }
@@ -146,6 +149,22 @@ class ASH_EXPORT WmShell {
     simulate_modal_window_open_for_testing_ = modal_window_open;
   }
 
+  // Shows the app list on the active root window.
+  void ShowAppList();
+
+  // Dismisses the app list.
+  void DismissAppList();
+
+  // Shows the app list if it's not visible. Dismisses it otherwise.
+  void ToggleAppList();

[msw, 2016/07/20 17:33:49]

optional nit: This only really has two callers (HandleToggleAppList in
accelerator_controller.cc and AppListShelfItemDelegate::ItemSelected); it could
be removed and those places could call into the presenter directly or inline
similar behavior and then even the presenter method could go away.

[James Cook, 2016/07/20 18:35:39]

I'm going to keep the applist functions as-is. It feels like either WmShell
should expose all 5, or it should just expose the AppListPresenter, and doing
the latter involving inlining the default-display-lookup code in a bunch of
places.

+
+  // Returns app list actual visibility. This might differ from
+  // GetAppListTargetVisibility() when hiding animation is still in flight.

[msw, 2016/07/20 17:33:49]

optional nit: It'd also be nice to only have a single function for visibility.

+  bool IsApplistVisible() const;
+
+  // Returns app list target visibility.
+  bool GetAppListTargetVisibility() const;
+
   // Returns true if a window is currently pinned.
   virtual bool IsPinned() = 0;
 
@@ -277,6 +296,7 @@ class ASH_EXPORT WmShell {
   std::unique_ptr<MaximizeModeController> maximize_mode_controller_;
   std::unique_ptr<MediaDelegate> media_delegate_;
   std::unique_ptr<MruWindowTracker> mru_window_tracker_;
+  std::unique_ptr<ShelfModel> shelf_model_;
   std::unique_ptr<SystemTrayNotifier> system_tray_notifier_;
   std::unique_ptr<SystemTrayDelegate> system_tray_delegate_;
   std::unique_ptr<WindowCycleController> window_cycle_controller_;