macOS Accessibility: Fixed crash due to availability of NSAccessibilityLayoutChangedNotification on < 10.9

modules/juce_gui_basics/native/accessibility/juce_mac_Accessibility.mm

@@ -31,6 +31,12 @@ namespace juce
  using NSAccessibilityNotificationName = NSString*;
 #endif
 
+#if (! defined MAC_OS_X_VERSION_10_9) || MAC_OS_X_VERSION_MAX_ALLOWED < MAC_OS_X_VERSION_10_9
+ const NSAccessibilityNotificationName NSAccessibilityLayoutChangedNotificationJuce = @"AXLayoutChanged";
+#else
+ const NSAccessibilityNotificationName NSAccessibilityLayoutChangedNotificationJuce = NSAccessibilityLayoutChangedNotification;
+#endif
+
 #if JUCE_OBJC_HAS_AVAILABLE_FEATURE || (defined (MAC_OS_X_VERSION_10_10) && MAC_OS_X_VERSION_MIN_REQUIRED >= MAC_OS_X_VERSION_10_10)
 
 #define JUCE_NATIVE_ACCESSIBILITY_INCLUDED 1
@@ -1071,7 +1077,7 @@ void notifyAccessibilityEventInternal (const AccessibilityHandler& handler, Inte
         {
             case InternalAccessibilityEvent::elementCreated:         return NSAccessibilityCreatedNotification;
             case InternalAccessibilityEvent::elementDestroyed:       return NSAccessibilityUIElementDestroyedNotification;
-            case InternalAccessibilityEvent::elementMovedOrResized:  return NSAccessibilityLayoutChangedNotification;
+            case InternalAccessibilityEvent::elementMovedOrResized:  return NSAccessibilityLayoutChangedNotificationJuce;
             case InternalAccessibilityEvent::focusChanged:           return NSAccessibilityFocusedUIElementChangedNotification;
             case InternalAccessibilityEvent::windowOpened:           return NSAccessibilityWindowCreatedNotification;
             case InternalAccessibilityEvent::windowClosed:           break;
@@ -1095,7 +1101,7 @@ void AccessibilityHandler::notifyAccessibilityEvent (AccessibilityEvent eventTyp
             case AccessibilityEvent::textChanged:
             case AccessibilityEvent::valueChanged:          return NSAccessibilityValueChangedNotification;
             case AccessibilityEvent::titleChanged:          return NSAccessibilityTitleChangedNotification;
-            case AccessibilityEvent::structureChanged:      return NSAccessibilityLayoutChangedNotification;
+            case AccessibilityEvent::structureChanged:      return NSAccessibilityLayoutChangedNotificationJuce;
         }
 
         return NSAccessibilityNotificationName{};