Add Hide and Show to the app list SearchBoxView.

ui/app_list/views/search_box_view.cc

Index: ui/app_list/views/search_box_view.cc
diff --git a/ui/app_list/views/search_box_view.cc b/ui/app_list/views/search_box_view.cc
index 557cc21758ff49e6f7497a92a8bc3b24d4c1357a..8dc136579f576475119ef9a9800bfc3cd866bc58 100644
--- a/ui/app_list/views/search_box_view.cc
+++ b/ui/app_list/views/search_box_view.cc
@@ -108,6 +108,16 @@ void SearchBoxView::InvalidateMenu() {
   menu_.reset();
 }
 
+void SearchBoxView::Show() {
+  SetVisible(true);
+  delegate_->SearchBoxVisibilityChanged(this);
+}
+
+void SearchBoxView::Hide() {
+  SetVisible(false);
+  delegate_->SearchBoxVisibilityChanged(this);
+}
+
 gfx::Size SearchBoxView::GetPreferredSize() {
   return gfx::Size(kPreferredWidth, kPreferredHeight);
 }