ash: Remove ShelfModel id conversion functions.

chrome/browser/ui/ash/launcher/arc_app_window_launcher_controller.cc

 // 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.
 #include "chrome/browser/ui/ash/launcher/arc_app_window_launcher_controller.h"
 
 #include <string>
 
 #include "ash/display/screen_orientation_controller_chromeos.h"
 #include "ash/public/cpp/window_properties.h"
 #include "ash/shared/app_types.h"
@@ skipping 636 matching lines @@
   if (it != app_shelf_group_to_controller_map_.end()) {
     DCHECK_EQ(it->second->app_id(), app_shelf_id.ToString());
     it->second->AddTaskId(task_id);
     return it->second;
   }
 
   std::unique_ptr<ArcAppWindowLauncherItemController> controller =
       base::MakeUnique<ArcAppWindowLauncherItemController>(
           app_shelf_id.ToString());
   ArcAppWindowLauncherItemController* item_controller = controller.get();
-  ash::ShelfModel* shelf_model = ash::Shell::Get()->shelf_model();
-  const ash::ShelfID shelf_id =
-      shelf_model->GetShelfIDForAppID(app_shelf_id.ToString());
-  if (shelf_id.IsNull()) {
+  const ash::ShelfID shelf_id(app_shelf_id.ToString());
+  if (owner()->GetItem(shelf_id) == nullptr) {

[James Cook, 2017/05/10 02:51:18]

Yeah, I think HasItem() would be easier to read.

"== nullptr" makes me think of Java code.

[msw, 2017/05/10 18:21:53]

I'm using TRUE/FALSE for test expectations, and I simplified this.

[James Cook, 2017/05/10 19:29:35]

Yeah, I think the TRUE/FALSE works well enough.

     owner()->CreateAppLauncherItem(std::move(controller), ash::STATUS_RUNNING);
   } else {
-    shelf_model->SetShelfItemDelegate(shelf_id, std::move(controller));
+    owner()->shelf_model()->SetShelfItemDelegate(shelf_id,
+                                                 std::move(controller));
     owner()->SetItemStatus(shelf_id, ash::STATUS_RUNNING);
   }
   item_controller->AddTaskId(task_id);
   app_shelf_group_to_controller_map_[app_shelf_id] = item_controller;
   return item_controller;
 }
 
 void ArcAppWindowLauncherController::RegisterApp(
     AppWindowInfo* app_window_info) {
   AppWindow* app_window = app_window_info->app_window();
   ArcAppWindowLauncherItemController* controller =
       AttachControllerToTask(app_window->task_id(), *app_window_info);
-  DCHECK(controller);
-
-  const ash::ShelfID shelf_id =
-      ash::Shell::Get()->shelf_model()->GetShelfIDForAppID(
-          controller->app_id());
-  DCHECK(!shelf_id.IsNull());
+  DCHECK(!controller->app_id().empty());
+  const ash::ShelfID shelf_id(controller->app_id());
+  DCHECK_NE(nullptr, owner()->GetItem(shelf_id));
 
   controller->AddWindow(app_window);
   owner()->SetItemStatus(shelf_id, ash::STATUS_RUNNING);
   app_window->SetController(controller);
   app_window->set_shelf_id(shelf_id);
 }
 
 void ArcAppWindowLauncherController::UnregisterApp(
     AppWindowInfo* app_window_info) {
   AppWindow* app_window = app_window_info->app_window();
@@ skipping 45 matching lines @@
   const std::string arc_app_id = exo::ShellSurface::GetApplicationId(window);
   if (arc_app_id.empty())
     return -1;
 
   int task_id = -1;
   if (sscanf(arc_app_id.c_str(), "org.chromium.arc.%d", &task_id) != 1)
     return -1;
 
   return task_id;
 }