cros: Fix mouse over-scroll animation not happening.

ui/app_list/apps_grid_view.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 "ui/app_list/apps_grid_view.h"
 
 #include <algorithm>
 
 #include "ui/app_list/app_list_item_view.h"
 #include "ui/app_list/pagination_model.h"
@@ skipping 74 matching lines @@
 }
 
 void AppsGridView::EnsureItemVisible(const AppListItemView* item) {
   int index = GetIndexOf(item);
   if (index >= 0 && tiles_per_page()) {
     pagination_model_->SelectPage(index / tiles_per_page(),
                                   false /* animate */);
   }
 }
 
+bool AppsGridView::HasPageTransition() const {
+  return pagination_model_->has_transition();
+}
+
 gfx::Size AppsGridView::GetPreferredSize() {
   gfx::Insets insets(GetInsets());
   gfx::Size tile_size = gfx::Size(kPreferredTileWidth, kPreferredTileHeight);
   return gfx::Size(tile_size.width() * cols_ + insets.width(),
                    tile_size.height() * rows_per_page_ + insets.height());
 }
 
 void AppsGridView::Layout() {
   gfx::Rect rect(GetContentsBounds());
   if (rect.IsEmpty() || child_count() == 0 || !tiles_per_page())
@@ skipping 228 matching lines @@
 void AppsGridView::TransitionChanged() {
   // Update layout for valid page transition only since over-scroll no longer
   // animates app icons.
   const PaginationModel::Transition& transition =
       pagination_model_->transition();
   if (pagination_model_->is_valid_page(transition.target_page))
     Layout();
 }
 
 }  // namespace app_list