QuickLook iOS 11.0 Beta 1 to Beta 2 API Differences

QLPreviewingController.h
Modified -[QLPreviewingController preparePreviewOfSearchableItemWithIdentifier:queryString:completionHandler:]
Declaration
From- (void)preparePreviewOfSearchableItemWithIdentifier:(nonnull NSString *)identifier queryString:(nullable NSString *)queryString completionHandler:(nonnull QLPreviewItemLoadingBlock)handler
To- (void)preparePreviewOfSearchableItemWithIdentifier:(nonnull NSString *)identifier queryString:(nullable NSString *)queryString completionHandler:(nonnull void (^)(NSError * _Nullable))handler

Modified -[QLPreviewingController preparePreviewOfFileAtURL:completionHandler:]
Declaration
From- (void)preparePreviewOfFileAtURL:(nonnull NSURL *)URL completionHandler:(nonnull QLPreviewItemLoadingBlock)handler
To- (void)preparePreviewOfFileAtURL:(nonnull NSURL *)url completionHandler:(nonnull void (^)(NSError * _Nullable))handler