Fix opt-in IME menu crash.

ash/common/system/tray/tray_details_view.cc

Index: ash/common/system/tray/tray_details_view.cc
diff --git a/ash/common/system/tray/tray_details_view.cc b/ash/common/system/tray/tray_details_view.cc
index 53235a675fe1f759d21c7e71081356c50d101761..35d58cdf2c722d78da1fa4631f843384c0fdb30c 100644
--- a/ash/common/system/tray/tray_details_view.cc
+++ b/ash/common/system/tray/tray_details_view.cc
@@ -75,7 +75,7 @@ TrayDetailsView::TrayDetailsView(SystemTrayItem* owner)
 TrayDetailsView::~TrayDetailsView() {}
 
 void TrayDetailsView::OnViewClicked(views::View* sender) {
-  if (!MaterialDesignController::IsSystemTrayMenuMaterial() &&
+  if (!MaterialDesignController::IsSystemTrayMenuMaterial() && title_row_ &&
       sender == title_row_->content()) {
     TransitionToDefaultView();
     return;