App list folder icons: Fixed off-by-one error.

ui/app_list/app_list_folder_item.cc

 // Copyright 2013 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 "ui/app_list/app_list_folder_item.h"
 
 #include "base/guid.h"
 #include "ui/app_list/app_list_constants.h"
 #include "ui/app_list/app_list_item_list.h"
 #include "ui/app_list/folder_image_source.h"
@@ skipping 21 matching lines @@
     top_icons.push_back(top_items_[i]->icon());
 
   const gfx::Size icon_size = gfx::Size(kGridIconDimension, kGridIconDimension);
   gfx::ImageSkia icon = gfx::ImageSkia(
       new FolderImageSource(top_icons, icon_size),
       icon_size);
   SetIcon(icon, false);
 }
 
 const gfx::ImageSkia& AppListFolderItem::GetTopIcon(size_t item_index) {
-  DCHECK(item_index <= top_items_.size());
+  CHECK_LT(item_index, top_items_.size());
   return top_items_[item_index]->icon();
 }
 
 gfx::Rect AppListFolderItem::GetTargetIconRectInFolderForItem(
     AppListItem* item,
     const gfx::Rect& folder_icon_bounds) {
   for (size_t i = 0; i < top_items_.size(); ++i) {
     if (item->id() == top_items_[i]->id()) {
       std::vector<gfx::Rect> rects =
           FolderImageSource::GetTopIconsBounds(folder_icon_bounds);
@@ skipping 53 matching lines @@
 std::string AppListFolderItem::GenerateId() {
   return base::GenerateGUID();
 }
 
 void AppListFolderItem::ItemIconChanged() {
   UpdateIcon();
 }
 
 void AppListFolderItem::OnListItemAdded(size_t index,
                                         AppListItem* item) {
-  if (index <= kNumFolderTopItems)
+  if (index < kNumFolderTopItems)
     UpdateTopItems();
 }
 
 void AppListFolderItem::OnListItemRemoved(size_t index,
                                           AppListItem* item) {
-  if (index <= kNumFolderTopItems)
+  if (index < kNumFolderTopItems)
     UpdateTopItems();
 }
 
 void AppListFolderItem::OnListItemMoved(size_t from_index,
                                         size_t to_index,
                                         AppListItem* item) {
-  if (from_index <= kNumFolderTopItems || to_index <= kNumFolderTopItems)
+  if (from_index < kNumFolderTopItems || to_index < kNumFolderTopItems)
     UpdateTopItems();
 }
 
 void AppListFolderItem::UpdateTopItems() {
   for (size_t i = 0; i < top_items_.size(); ++i)
     top_items_[i]->RemoveObserver(this);
   top_items_.clear();
 
   for (size_t i = 0;
        i < kNumFolderTopItems && i < item_list_->item_count(); ++i) {
     AppListItem* item = item_list_->item_at(i);
     item->AddObserver(this);
     top_items_.push_back(item);
   }
   UpdateIcon();
 }
 
 }  // namespace app_list