Add `accessibilityContext` to CKOverlayLayoutComponent

Summary: Changelog: [Internal]

Reviewed By: Andrey-Mishanin

Differential Revision: D38906662

fbshipit-source-id: f0501f48df6a9debebd9211d388c6c89d29d149d

Libraries/SurfaceBackedComponent/RCTSurfaceBackedComponent.mm

@@ -70,7 +70,8 @@
     component = surfaceHostingComponent;
   } else {
     component = [[CKOverlayLayoutComponent alloc] initWithComponent:surfaceHostingComponent
-                                                            overlay:options.activityIndicatorComponentFactory()];
+                                                            overlay:options.activityIndicatorComponentFactory()
+                                               accessibilityContext:{}];
   }
 
   return [super newWithComponent:component];