fix(test): stabilize prevent-default-twice notification generation tests

Remove notification.display() after the second preventDefault(true). The
display waiter uses a CONFLATED channel; display() wakes with true and
overwrites preventDefault(true)'s wake(false), so the processor could
still call displayNotification — flaky on fast CI (see PR #2605).

Clarify IOMockHelper KDoc: top-level launchOnIO is not stubbed; only
OneSignalDispatchers.launchOnIO is.

Made-with: Cursor

Author: AR Abdul Azeez

OneSignalSDK/onesignal/notifications/src/test/java/com/onesignal/notifications/internal/generation/NotificationGenerationProcessorTests.kt

@@ -288,8 +288,9 @@ class NotificationGenerationProcessorTests : FunSpec({
             val willDisplayEvent = firstArg<INotificationWillDisplayEvent>()
             willDisplayEvent.preventDefault(false)
             suspendifyOnIO {
+                // Second preventDefault(true) wakes the waiter with false; avoid notification.display()
+                // which would wake(true) and overwrite the conflated channel (CI flake on fast runners).
                 willDisplayEvent.preventDefault(true)
-                willDisplayEvent.notification.display()
             }
         }
 
@@ -311,7 +312,6 @@ class NotificationGenerationProcessorTests : FunSpec({
             receivedEvent.preventDefault(false)
             suspendifyOnIO {
                 receivedEvent.preventDefault(true)
-                receivedEvent.notification.display()
             }
         }
 

OneSignalSDK/onesignal/testhelpers/src/main/java/com/onesignal/mocks/IOMockHelper.kt

@@ -31,7 +31,8 @@ import java.util.concurrent.atomic.AtomicInteger
  * (e.g., delay(50)) to wait for async work to finish.
  *
  * This helper avoids that by:
- *  - Mocking `suspendifyOnIO`, `launchOnIO`, and `launchOnDefault` so their blocks run immediately
+ *  - Mocking `suspendifyOnIO`, `suspendifyOnMain`, and `OneSignalDispatchers.launchOnIO` /
+ *    `launchOnDefault` so their blocks run immediately
  *  - Completing a `CompletableDeferred` when the async block finishes
  *  - Providing `awaitIO()` so tests can explicitly wait for all async work without sleeps
  *