NSViewComponentPeer: Fix use-after-free when closing windows with the keyboard

Author: reuk

modules/juce_gui_basics/native/juce_NSViewComponentPeer_mac.mm

@@ -2333,9 +2333,14 @@ static id getAccessibleChild (id self)
         {
             if (auto* owner = getOwner (self))
             {
-                const ScopedValueSetter scope { owner->inPerformKeyEquivalent, true };
-
                 const auto ref = owner->safeComponent;
+                const auto prev = std::exchange (owner->inPerformKeyEquivalent, true);
+
+                const ScopeGuard scope { [&ref, owner, prev]
+                {
+                    if (ref != nullptr)
+                        owner->inPerformKeyEquivalent = prev;
+                } };
 
                 if (owner->sendEventToInputContextOrComponent (ev))
                 {