fix: MPAppNotificationHandler webpageURL issue (#353)

Author: BrandonStalnaker

UnitTests/MPAppNotificationHandlerTests.m

@@ -84,4 +84,19 @@ - (void)testOpenURLOptions {
     [appNotificationHandler openURL:url options:options];
 }
 
+- (void)testContinueUserActivityNoCrash {
+    MPAppNotificationHandler *appNotificationHandler = [MParticle sharedInstance].appNotificationHandler;
+    
+    NSUserActivity *userActivity = [[NSUserActivity alloc] initWithActivityType:@"test"];
+    userActivity.webpageURL = [[NSURL alloc] initWithString:@"http://mparticle.com"];
+    [appNotificationHandler continueUserActivity:userActivity restorationHandler:^(NSArray<id<UIUserActivityRestoring>> *restorationHandler){}];
+}
+
+- (void)testContinueUserActivityWithNilURLNoCrash {
+    MPAppNotificationHandler *appNotificationHandler = [MParticle sharedInstance].appNotificationHandler;
+    
+    NSUserActivity *userActivity = [[NSUserActivity alloc] initWithActivityType:@"test"];
+    [appNotificationHandler continueUserActivity:userActivity restorationHandler:^(NSArray<id<UIUserActivityRestoring>> *restorationHandler){}];
+}
+
 @end

mParticle-Apple-SDK/AppNotifications/MPAppNotificationHandler.m

@@ -281,7 +281,12 @@ - (BOOL)continueUserActivity:(nonnull NSUserActivity *)userActivity restorationH
         return NO;
     }
 
-    stateMachine.launchInfo = [[MPLaunchInfo alloc] initWithURL:userActivity.webpageURL options:nil];
+    if (userActivity.webpageURL != nil) {
+        stateMachine.launchInfo = [[MPLaunchInfo alloc] initWithURL:userActivity.webpageURL options:nil];
+    } else {
+        NSURL *defaultURL = [[NSURL alloc] initWithString:@""];
+        stateMachine.launchInfo = [[MPLaunchInfo alloc] initWithURL:defaultURL options:nil];
+    }
 
     SEL continueUserActivitySelector = @selector(continueUserActivity:restorationHandler:);