Added back button when in folder view.

ui/app_list/views/contents_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/views/contents_view.h"
 
 #include <algorithm>
 #include <vector>
 
 #include "base/logging.h"
@@ skipping 20 matching lines @@
 
 ContentsView::ContentsView(AppListMainView* app_list_main_view,
                            AppListView* app_list_view)
     : model_(nullptr),
       apps_container_view_(nullptr),
       search_results_page_view_(nullptr),
       start_page_view_(nullptr),
       custom_page_view_(nullptr),
       app_list_main_view_(app_list_main_view),
       app_list_view_(app_list_view),
-      page_before_search_(0) {
+      page_before_search_(0),
+      is_fullscreen_app_list_enabled_(features::IsFullscreenAppListEnabled()) {
   pagination_model_.SetTransitionDurations(kPageTransitionDurationInMs,
                                            kOverscrollPageTransitionDurationMs);
   pagination_model_.AddObserver(this);
 }
 
 ContentsView::~ContentsView() {
   pagination_model_.RemoveObserver(this);
 }
 
 void ContentsView::Init(AppListModel* model) {
@@ skipping 151 matching lines @@
   if (it != view_to_state_.end())
     state = it->second;
 
   app_list_pages_[GetActivePageIndex()]->OnWillBeShown();
 
   app_list_main_view_->model()->SetState(state);
 
   DCHECK(start_page_view_);
 
   // Set the visibility of the search box's back button.
-  if (!features::IsFullscreenAppListEnabled()) {
+  const bool folder_active = state == AppListModel::STATE_APPS &&
+                             apps_container_view_->IsInFolderView();
+
+  if (!is_fullscreen_app_list_enabled_) {
     app_list_main_view_->search_box_view()->back_button()->SetVisible(
         state != AppListModel::STATE_START);
     app_list_main_view_->search_box_view()->Layout();
-    bool folder_active = (state == AppListModel::STATE_APPS)
-                             ? apps_container_view_->IsInFolderView()
-                             : false;
     app_list_main_view_->search_box_view()->SetBackButtonLabel(folder_active);
   }
 
   // Whenever the page changes, the custom launcher page is considered to have
   // been reset.
   app_list_main_view_->model()->ClearCustomLauncherPageSubpages();
   app_list_main_view_->search_box_view()->ResetTabFocus(false);
 }
 
 void ContentsView::ShowSearchResults(bool show) {
@@ skipping 255 matching lines @@
 }
 
 void ContentsView::TransitionStarted() {
 }
 
 void ContentsView::TransitionChanged() {
   UpdatePageBounds();
 }
 
 }  // namespace app_list