ash: Remove ShelfModel id conversion functions.

ash/shelf/shelf_view_unittest.cc

 // Copyright (c) 2012 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 "ash/shelf/shelf_view.h"
 
 #include <algorithm>
 #include <memory>
 #include <utility>
 #include <vector>
@@ skipping 290 matching lines @@
     }
     test_api_->RunMessageLoopUntilAnimationsDone();
   }
 
   void RemoveByID(const ShelfID& id) {
     model_->RemoveItemAt(model_->ItemIndexByID(id));
     test_api_->RunMessageLoopUntilAnimationsDone();
   }
 
   ShelfButton* GetButtonByID(const ShelfID& id) {
-    int index = model_->ItemIndexByID(id);
-    return test_api_->GetButton(index);
+    return test_api_->GetButton(model_->ItemIndexByID(id));
   }
 
-  ShelfItem GetItemByID(const ShelfID& id) {
-    ShelfItems::const_iterator items = model_->ItemByID(id);
-    return *items;
-  }
+  ShelfItem GetItemByID(const ShelfID& id) { return *model_->ItemByID(id); }
 
   void CheckModelIDs(
       const std::vector<std::pair<ShelfID, views::View*>>& id_map) {
     size_t map_index = 0;
     for (size_t model_index = 0; model_index < model_->items().size();
          ++model_index) {
       ShelfItem item = model_->items()[model_index];
       ShelfID id = item.id;
       EXPECT_EQ(id_map[map_index].first, id);
       EXPECT_EQ(id_map[map_index].second, GetButtonByID(id));
@@ skipping 298 matching lines @@
     }
     test_api_->HideOverflowBubble();
   }
 
   // Returns the item's ShelfID at |index|.
   ShelfID GetItemId(int index) {
     DCHECK_GE(index, 0);
     return model_->items()[index].id;
   }
 
-  // Returns the center coordinates for a button. Helper function for an event
-  // generator.
+  // Returns the center point of a button. Helper function for event generators.
   gfx::Point GetButtonCenter(const ShelfID& button_id) {
-    return GetButtonCenter(
-        test_api_->GetButton(model_->ItemIndexByID(button_id)));
+    return GetButtonCenter(GetButtonByID(button_id));
   }
 
   gfx::Point GetButtonCenter(ShelfButton* button) {
     return button->GetBoundsInScreen().CenterPoint();
   }
 
   ShelfModel* model_ = nullptr;
   ShelfView* shelf_view_ = nullptr;
   int browser_index_ = 1;
   bool reach_touch_time_threshold_ = true;
@@ skipping 2465 matching lines @@
   EXPECT_EQ(views::InkDropState::ACTIVATED,
             overflow_button_ink_drop_->GetTargetInkDropState());
   EXPECT_THAT(overflow_button_ink_drop_->GetAndResetRequestedStates(),
               IsEmpty());
 
   ASSERT_TRUE(test_api_->IsShowingOverflowBubble());
 }
 
 }  // namespace test
 }  // namespace ash