Change MenuControllerDelegate to provide WeakPtr

ui/views/controls/menu/menu_controller.cc

Index: ui/views/controls/menu/menu_controller.cc
diff --git a/ui/views/controls/menu/menu_controller.cc b/ui/views/controls/menu/menu_controller.cc
index aa002f26882d79ca43b067baf83c580db4b26f93..a3b11ed50d04a03382598f71d5f036597a9bed71 100644
--- a/ui/views/controls/menu/menu_controller.cc
+++ b/ui/views/controls/menu/menu_controller.cc
@@ -522,8 +522,11 @@ void MenuController::Cancel(ExitType type) {
     // triggers deleting us.
     DCHECK(selected);
     showing_ = false;
-    delegate_->OnMenuClosed(internal::MenuControllerDelegate::NOTIFY_DELEGATE,
-                            selected->GetRootMenuItem(), accept_event_flags_);
+    // Verify that the delegate was not destroyed.
+    if (delegate_) {
+      delegate_->OnMenuClosed(internal::MenuControllerDelegate::NOTIFY_DELEGATE,
+                              selected->GetRootMenuItem(), accept_event_flags_);
+    }
     // WARNING: the call to MenuClosed deletes us.
     return;
   }
@@ -544,8 +547,8 @@ void MenuController::Cancel(ExitType type) {
 
 void MenuController::AddNestedDelegate(
     internal::MenuControllerDelegate* delegate) {
-  delegate_stack_.push_back(std::make_pair(delegate, async_run_));
-  delegate_ = delegate;
+  delegate_stack_.push_back(std::make_pair(delegate->AsWeakPtr(), async_run_));
+  delegate_ = delegate->AsWeakPtr();
 }
 
 void MenuController::SetAsyncRun(bool is_async) {
@@ -978,7 +981,7 @@ int MenuController::OnPerformDrop(SubmenuView* source,
   if (drop_target->id() == MenuItemView::kEmptyMenuItemViewID)
     drop_target = drop_target->GetParentMenuItem();
 
-  if (!IsBlockingRun()) {
+  if (!IsBlockingRun() && delegate_) {
     delegate_->OnMenuClosed(
         internal::MenuControllerDelegate::DONT_NOTIFY_DELEGATE,
         item->GetRootMenuItem(), accept_event_flags_);
@@ -1395,7 +1398,7 @@ MenuController::MenuController(bool blocking,
       showing_submenu_(false),
       active_mouse_view_id_(ViewStorage::GetInstance()->CreateStorageID()),
       hot_button_(nullptr),
-      delegate_(delegate),
+      delegate_(delegate->AsWeakPtr()),
       message_loop_depth_(0),
       async_run_(false),
       is_combobox_(false),
@@ -1522,7 +1525,8 @@ bool MenuController::ShowSiblingMenu(SubmenuView* source,
   if (!alt_menu || (state_.item && state_.item->GetRootMenuItem() == alt_menu))
     return false;
 
-  delegate_->SiblingMenuCreated(alt_menu);
+  if (delegate_)
+    delegate_->SiblingMenuCreated(alt_menu);
 
   if (!button) {
     // If the delegate returns a menu, they must also return a button.
@@ -2585,15 +2589,18 @@ void MenuController::ExitAsyncRun() {
     return;
   bool nested = delegate_stack_.size() > 1;
   // ExitMenuRun unwinds nested delegates
-  internal::MenuControllerDelegate* delegate = delegate_;
+  base::WeakPtr<internal::MenuControllerDelegate> delegate = delegate_;
   // MenuController may have been deleted when releasing ViewsDelegate ref.
   // However as |delegate| can outlive this, it must still be notified of the
   // menu closing so that it can perform teardown.
   int accept_event_flags = accept_event_flags_;
   base::WeakPtr<MenuController> this_ref = AsWeakPtr();
   MenuItemView* result = ExitMenuRun();
-  delegate->OnMenuClosed(internal::MenuControllerDelegate::NOTIFY_DELEGATE,
-                         result, accept_event_flags);
+  // The delegate may have been deleted.
+  if (delegate) {
+    delegate->OnMenuClosed(internal::MenuControllerDelegate::NOTIFY_DELEGATE,
+                           result, accept_event_flags);
+  }
   // |delegate| may have deleted this.
   if (this_ref && nested && exit_type_ == EXIT_ALL)
     ExitAsyncRun();