swift5 new compiler nits

Signal/src/UserInterface/HapticFeedback.swift

@@ -51,6 +51,7 @@ enum NotificationHapticFeedbackType {
     case error, success, warning
 }
 
+@available(iOS 10.0, *)
 extension NotificationHapticFeedbackType {
     var uiNotificationFeedbackType: UINotificationFeedbackGenerator.FeedbackType {
         switch self {

SignalShareExtension/ShareViewController.swift

@@ -23,7 +23,7 @@ public class ShareViewController: UIViewController, ShareViewDelegate, SAEFailed
     enum ShareViewControllerError: Error {
         case assertionError(description: String)
         case unsupportedMedia
-        case notRegistered()
+        case notRegistered
         case obsoleteShare
     }
 
@@ -475,7 +475,7 @@ public class ShareViewController: UIViewController, ShareViewDelegate, SAEFailed
             // If root view is an error view, do nothing.
             return
         }
-        throw ShareViewControllerError.notRegistered()
+        throw ShareViewControllerError.notRegistered
     }
 
     // MARK: ShareViewDelegate, SAEFailedViewDelegate