Preload accessibility framework if not already loaded

Summary:
It looks like there are some edge cases when app did not load private accessibility framework (probably if it never set any accessibility values?)

This diff makes calls to accessibility hierarchy safer and ensures to preload framework if available

Reviewed By: lblasa

Differential Revision: D49501064

fbshipit-source-id: b46216b58bf6c9c63f900e199fea035e3262afb2

iOS/Plugins/FlipperKitUIDebuggerPlugin/FlipperKitUIDebuggerPlugin/Serializers/UIDInitEvent+Foundation.m

@@ -8,6 +8,7 @@
 #if FB_SONARKIT_ENABLED
 
 #import "NSArray+Foundation.h"
+#import "UIDAllyTraversal.h"
 #import "UIDInitEvent+Foundation.h"
 #import "UIDTraversalMode.h"
 
@@ -20,12 +21,15 @@ FB_LINKABLE(UIDInitEvent_Foundation)
     @"frameworkEventMetadata" : self.frameworkEventMetadata
         ? [self.frameworkEventMetadata toFoundation]
         : @[],
-    @"supportedTraversalModes" : @[
+    @"supportedTraversalModes" : UIDAllyTraversal.isSupported ? @[
       NSStringFromUIDTraversalMode(UIDTraversalModeViewHierarchy),
       NSStringFromUIDTraversalMode(UIDTraversalModeAccessibilityHierarchy),
+    ] : @[
+      NSStringFromUIDTraversalMode(UIDTraversalModeViewHierarchy),
     ],
-    @"currentTraversalMode" :
-        NSStringFromUIDTraversalMode(self.currentTraversalMode),
+    @"currentTraversalMode" : NSStringFromUIDTraversalMode(
+        UIDAllyTraversal.isSupported ? self.currentTraversalMode
+                                     : UIDTraversalModeViewHierarchy),
   };
 }