Add Hide and Show to the app list SearchBoxView.

ui/app_list/views/app_list_background.cc

Index: ui/app_list/views/app_list_background.cc
diff --git a/ui/app_list/views/app_list_background.cc b/ui/app_list/views/app_list_background.cc
index 9e4dced9450aa06a8698b6d1beded2a42dea7066..a3c3b9de5c0b6077f42439662b8c672dc2c8f30e 100644
--- a/ui/app_list/views/app_list_background.cc
+++ b/ui/app_list/views/app_list_background.cc
@@ -55,8 +55,8 @@ void AppListBackground::Paint(gfx::Canvas* canvas,
   paint.setStyle(SkPaint::kFill_Style);
 
   int contents_top = bounds.y();
-  if (main_view_->visible()) {
-    views::View* search_box_view = main_view_->search_box_view();
+  views::View* search_box_view = main_view_->search_box_view();
+  if (main_view_->visible() && search_box_view->visible()) {
     const gfx::Rect search_box_view_bounds =
         search_box_view->ConvertRectToWidget(search_box_view->GetLocalBounds());
     gfx::Rect search_box_rect(bounds.x(),