ash: Do not show the arrow in the tray bubbles when the tray isn't visible.

ash/wm/shelf_layout_manager.cc

Index: ash/wm/shelf_layout_manager.cc
diff --git a/ash/wm/shelf_layout_manager.cc b/ash/wm/shelf_layout_manager.cc
index 6af5daf2ec8ba4d0e2d752c72d50466f8679c938..2e17bbfae0a39cb6ba81e5c6f649efd6ce74c9aa 100644
--- a/ash/wm/shelf_layout_manager.cc
+++ b/ash/wm/shelf_layout_manager.cc
@@ -124,6 +124,12 @@ void ShelfLayoutManager::SetAutoHideBehavior(ShelfAutoHideBehavior behavior) {
   UpdateVisibilityState();
 }
 
+bool ShelfLayoutManager::IsVisible() const {
+  return state_.visibility_state == VISIBLE ||
+      (state_.visibility_state == AUTO_HIDE &&
+       state_.auto_hide_state == AUTO_HIDE_SHOWN);
+}
+
 gfx::Rect ShelfLayoutManager::GetMaximizedWindowBounds(
     aura::Window* window) const {
   // TODO: needs to be multi-mon aware.