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 192 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.
+  bool folder_active = (state == AppListModel::STATE_APPS)

[vadimt, 2017/06/22 00:36:12]

state == AppListModel::STATE_APPS &&
                            ? apps_container_view_->IsInFolderView()

[newcomer, 2017/06/22 16:49:06]

Done.

+                           ? apps_container_view_->IsInFolderView()
+                           : false;
   if (!features::IsFullscreenAppListEnabled()) {
     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);
+  } else {
+    if (app_list_main_view()->Contains(app_list_main_view()->search_box_view()))
+      app_list_main_view_->search_box_view()->SwapGoogleIconWithBackButton(

[vadimt, 2017/06/22 00:36:12]

{}

[newcomer, 2017/06/22 16:49:06]

Done.

+          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) {
   int search_page = GetPageIndexForState(AppListModel::STATE_SEARCH_RESULTS);
@@ skipping 254 matching lines @@
 }
 
 void ContentsView::TransitionStarted() {
 }
 
 void ContentsView::TransitionChanged() {
   UpdatePageBounds();
 }
 
 }  // namespace app_list