Experimental app list: "All apps" button has a folder-like icon.

ui/app_list/views/start_page_view.cc

 // Copyright 2014 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/views/start_page_view.h"
 
 #include "base/strings/utf_string_conversions.h"
 #include "ui/app_list/app_list_constants.h"
 #include "ui/app_list/app_list_item.h"
 #include "ui/app_list/app_list_model.h"
@@ skipping 126 matching lines @@
 
   // Add SearchResultTileItemViews to the container.
   for (size_t i = 0; i < std::max(kNumStartPageTiles, kNumSearchResultTiles);
        ++i) {
     SearchResultTileItemView* tile_item = new SearchResultTileItemView();
     tiles_container_->AddChildView(tile_item);
     search_result_tile_views_.push_back(tile_item);
   }
 
   // Also add a special "all apps" button to the end of the container.
-  all_apps_button_ =
-      new AllAppsTileItemView(app_list_main_view_->contents_view());
+  all_apps_button_ = new AllAppsTileItemView(
+      app_list_main_view_->contents_view(),
+      view_delegate_->GetModel()->top_level_item_list());
+  all_apps_button_->UpdateIcon();
   tiles_container_->AddChildView(all_apps_button_);
 }
 
 void StartPageView::SetModel(AppListModel* model) {
   DCHECK(model);
   if (search_results_model_)
     search_results_model_->RemoveObserver(this);
   search_results_model_ = model->results();
   search_results_model_->AddObserver(this);
   results_view_->SetResults(search_results_model_);
@@ skipping 115 matching lines @@
 
 void StartPageView::ListItemMoved(size_t index, size_t target_index) {
   ScheduleUpdate();
 }
 
 void StartPageView::ListItemsChanged(size_t start, size_t count) {
   ScheduleUpdate();
 }
 
 }  // namespace app_list