Xiaomi fix notification click not foregrounding

This fixes a bug where tapping on a OneSignal notification on a Xiaomi
device doesn't bring the app to the foreground.
Xiaomi has very strict activity trampolining rules on notification
open. We have to start the next activity before the current activity is
finished.

Tested on Xiaomi Redmi 6A device with MIUI 11.0.8 (Android 9) as well
as an Android 14 emulator.

OneSignalSDK/onesignal/notifications/src/main/java/com/onesignal/notifications/activities/NotificationOpenedActivityBase.kt

@@ -36,32 +36,26 @@ import com.onesignal.notifications.internal.open.INotificationOpenedProcessor
 abstract class NotificationOpenedActivityBase : Activity() {
     override fun onCreate(savedInstanceState: Bundle?) {
         super.onCreate(savedInstanceState)
-        if (!OneSignal.initWithContext(applicationContext)) {
-            return
-        }
-
-        var self = this
-
-        suspendifyOnThread {
-            var openedProcessor = OneSignal.getService<INotificationOpenedProcessor>()
-            openedProcessor.processFromContext(self, intent)
-        }
-
-        finish()
+        processIntent()
     }
 
     override fun onNewIntent(intent: Intent) {
         super.onNewIntent(intent)
+        processIntent()
+    }
+
+    private fun processIntent() {
         if (!OneSignal.initWithContext(applicationContext)) {
             return
         }
-
-        var self = this
         suspendifyOnThread {
-            var openedProcessor = OneSignal.getService<INotificationOpenedProcessor>()
-            openedProcessor.processFromContext(self, getIntent())
+            val openedProcessor = OneSignal.getService<INotificationOpenedProcessor>()
+            openedProcessor.processFromContext(this, intent)
+            // KEEP: Xiaomi Compatibility:
+            // Must keep this Activity alive while trampolining, that is
+            // startActivity() must be called BEFORE finish(), otherwise
+            // the app is never foregrounded.
+            finish()
         }
-
-        finish()
     }
 }