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

components/exo/shell_surface.cc

Index: components/exo/shell_surface.cc
diff --git a/components/exo/shell_surface.cc b/components/exo/shell_surface.cc
index f82d99403334a0ac8f36e9dc8b9278f50a610d66..10efe727153569f65763e70a2f63d143f92155cd 100644
--- a/components/exo/shell_surface.cc
+++ b/components/exo/shell_surface.cc
@@ -50,14 +50,6 @@
     {ui::VKEY_W, ui::EF_SHIFT_DOWN | ui::EF_CONTROL_DOWN},
     {ui::VKEY_F4, ui::EF_ALT_DOWN}};
 
-void UpdateShelfStateForFullscreenChange(views::Widget* widget) {
-  ash::wm::WindowState* window_state =
-      ash::wm::GetWindowState(widget->GetNativeWindow());
-  window_state->set_shelf_mode_in_fullscreen(
-      ash::wm::WindowState::SHELF_AUTO_HIDE_INVISIBLE);
-  ash::Shell::GetInstance()->UpdateShelfVisibility();
-}
-
 class CustomFrameView : public views::NonClientFrameView {
  public:
   explicit CustomFrameView(views::Widget* widget) : widget_(widget) {}
@@ -126,7 +118,6 @@
     if (widget_) {
       bool enter_fullscreen = !window_state->IsFullscreen();
       widget_->SetFullscreen(enter_fullscreen);
-      UpdateShelfStateForFullscreenChange(widget_);
     }
     return true;
   }
@@ -399,7 +390,6 @@
   // state doesn't change.
   ScopedConfigure scoped_configure(this, true);
   widget_->SetFullscreen(fullscreen);
-  UpdateShelfStateForFullscreenChange(widget_);
 }
 
 void ShellSurface::SetPinned(bool pinned) {