[PlayerModel] [Fix] make taskQueueWaitingForInit thread safe

[jkasten2]

Description

One Line Summary

Fix rare null crash with taskQueueWaitingForInit.poll() by making taskQueueWaitingForInit thread safe.

Details

Motivation

A few customers get this rare NPE crash.

Scope

Only affects calls made to OneSignal before the SDK is initialized.

Related Issues

#1761

Crash Example

java.lang.NullPointerException
  at java.util.concurrent.AbstractExecutorService.submit(AbstractExecutorService.java:116)
  at java.util.concurrent.Executors$DelegatedExecutorService.submit(Executors.java:640)
  at com.onesignal.OSTaskController.startPendingTasks(OSTaskController.java:92)
  at com.onesignal.OSTaskController.$$c(OSTaskController.java:92)
  at com.onesignal.OneSignal.init(OneSignal.java:885)
  at com.onesignal.OneSignal.setAppId(OneSignal.java:737)
  at com.onesignal.OneSignal.reassignDelayedInitParams(OneSignal.java:1180)
  at com.onesignal.OneSignal.onRemoteParamSet(OneSignal.java:889)
  at com.onesignal.OneSignal$7.complete(OneSignal.java:1121)
  at com.onesignal.OneSignalRemoteParams.processJson(OneSignalRemoteParams.java:211)
  at com.onesignal.OneSignalRemoteParams.access$100(OneSignalRemoteParams.java:12)
  at com.onesignal.OneSignalRemoteParams$1.onSuccess(OneSignalRemoteParams.java:156)
  at com.onesignal.OneSignalRestClient$5.run(OneSignalRestClient.java:279)
  at java.lang.Thread.run(Thread.java:922)

Testing

Manual testing

Tested on an Android 14 emulator ensuring a few things work like addTags.

Affected code checklist

• Notifications
  • Display
  • Open
  • Push Processing
  • Confirm Deliveries
• Outcomes
• Sessions
• In-App Messaging
• REST API requests
• Public API changes

Checklist

Overview

• I have filled out all REQUIRED sections above
• PR does one thing
  • If it is hard to explain how any codes changes are related to each other then it most likely needs to be more than one PR
• Any Public API changes are explained in the PR details and conform to existing APIs

Testing

• I have included test coverage for these changes, or explained why they are not needed
• All automated tests pass, or I explained why that is not possible
  • Tests were already failing on player-model-main
• I have personally tested this on my device, or explained why that is not possible

Final pass

• Code is as readable as possible.
  • Simplify with less code, followed by splitting up code into well named functions and variables, followed by adding comments to the code.
• I have reviewed this PR myself, ensuring it meets each checklist item
  • WIP (Work In Progress) is ok, but explain what is still in progress and what you would like feedback on. Start the PR title with "WIP" to indicate this.

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