Revert of Correctly handle tab navigation in the app list.

ui/app_list/views/app_list_view.cc

Index: ui/app_list/views/app_list_view.cc
diff --git a/ui/app_list/views/app_list_view.cc b/ui/app_list/views/app_list_view.cc
index 216abf4d4505b16a46ee4977aada5e6bc56ef716..c1bdb1edb175a75e3b73c46b380c1638611d966b 100644
--- a/ui/app_list/views/app_list_view.cc
+++ b/ui/app_list/views/app_list_view.cc
@@ -83,25 +83,6 @@
   return true;
 }
 
-// This view forwards the focus to the search box widget by providing it as a
-// FocusTraversable when a focus search is provided.
-class SearchBoxFocusHost : public views::View {
- public:
-  explicit SearchBoxFocusHost(views::Widget* search_box_widget)
-      : search_box_widget_(search_box_widget) {}
-
-  ~SearchBoxFocusHost() override {}
-
-  views::FocusTraversable* GetFocusTraversable() override {
-    return search_box_widget_;
-  }
-
- private:
-  views::Widget* search_box_widget_;
-
-  DISALLOW_COPY_AND_ASSIGN(SearchBoxFocusHost);
-};
-
 // The view for the App List overlay, which appears as a white rounded
 // rectangle with the given radius.
 class AppListOverlayView : public views::View {
@@ -201,7 +182,6 @@
     : delegate_(delegate),
       app_list_main_view_(nullptr),
       speech_view_(nullptr),
-      search_box_focus_host_(nullptr),
       search_box_widget_(nullptr),
       search_box_view_(nullptr),
       overlay_view_(nullptr),
@@ -482,15 +462,6 @@
   search_box_widget_ = new views::Widget;
   search_box_widget_->Init(search_box_widget_params);
   search_box_widget_->SetContentsView(search_box_view_);
-
-  // The search box will not naturally receive focus by itself (because it is in
-  // a separate widget). Create this SearchBoxFocusHost in the main widget to
-  // forward the focus search into to the search box.
-  search_box_focus_host_ = new SearchBoxFocusHost(search_box_widget_);
-  AddChildView(search_box_focus_host_);
-  search_box_widget_->SetFocusTraversableParentView(search_box_focus_host_);
-  search_box_widget_->SetFocusTraversableParent(
-      GetWidget()->GetFocusTraversable());
 
 #if defined(USE_AURA)
   // Mouse events on the search box shadow should not be captured.