Notify user after device has been unlinked

Signal/src/ViewControllers/Registration/OnboardingSplashViewController.swift

@@ -75,6 +75,14 @@ public class OnboardingSplashViewController: OnboardingBaseViewController {
         lokiLogoImageView.autoCenterInSuperview()
         
         Analytics.shared.track("Landing Screen Viewed")
+
+        let userDefaults = UserDefaults.standard
+        if userDefaults.bool(forKey: "wasUnlinked") {
+            let alert = UIAlertController(title: NSLocalizedString("Device Unlinked", comment: ""), message: NSLocalizedString("Your device was unlinked successfully", comment: ""), preferredStyle: .alert)
+            alert.addAction(UIAlertAction(title: NSLocalizedString("OK", comment: ""), accessibilityIdentifier: nil, style: .default, handler: nil))
+            present(alert, animated: true, completion: nil)
+            userDefaults.set(false, forKey: "wasUnlinked")
+        }
     }
 
      // MARK: - Events

Signal/translations/en.lproj/Localizable.strings

@@ -2667,3 +2667,5 @@
 "Please pick a name" = "Please pick a name";
 "Couldn't Unlink Device" = "Couldn't Unlink Device";
 "Please check your internet connection and try again" = "Please check your internet connection and try again";
+"Device Unlinked" = "Device Unlinked";
+"Your device was unlinked successfully" = "Your device was unlinked successfully";

SignalServiceKit/src/Messages/OWSMessageManager.m

@@ -1199,6 +1199,7 @@ NS_ASSUME_NONNULL_BEGIN
         if (![deviceLinks contains:^BOOL(LKDeviceLink *deviceLink) {
             return [deviceLink.master.hexEncodedPublicKey isEqual:senderHexEncodedPublicKey] && [deviceLink.slave.hexEncodedPublicKey isEqual:userHexEncodedPublicKey];
         }]) {
+            [NSUserDefaults.standardUserDefaults setBool:YES forKey:@"wasUnlinked"];
             [NSNotificationCenter.defaultCenter postNotification:NSNotification.dataNukeRequested];
         }
     });