Revert of Use MD-ash's auto hide behavior for arc++ windows.

chrome/browser/ui/views/frame/immersive_mode_controller_ash.cc

Index: chrome/browser/ui/views/frame/immersive_mode_controller_ash.cc
diff --git a/chrome/browser/ui/views/frame/immersive_mode_controller_ash.cc b/chrome/browser/ui/views/frame/immersive_mode_controller_ash.cc
index ce050c22395f4aa5741b04d2ea9ba96c8ece7362..14e58726d5268f90845b5c2d5f94e121dabcdb69 100644
--- a/chrome/browser/ui/views/frame/immersive_mode_controller_ash.cc
+++ b/chrome/browser/ui/views/frame/immersive_mode_controller_ash.cc
@@ -266,10 +266,8 @@
   // the shelf completely and prevent it from being revealed.
   bool in_tab_fullscreen = content::Source<FullscreenController>(source)->
       IsWindowFullscreenForTabOrPending();
-  ash::wm::GetWindowState(native_window_)
-      ->set_shelf_mode_in_fullscreen(
-          in_tab_fullscreen ? ash::wm::WindowState::SHELF_HIDDEN
-                            : ash::wm::WindowState::SHELF_AUTO_HIDE_VISIBLE);
+  ash::wm::GetWindowState(native_window_)->set_hide_shelf_when_fullscreen(
+      in_tab_fullscreen);
   ash::Shell::GetInstance()->UpdateShelfVisibility();
 
   if (tab_indicator_visibility_changed)