Enable the thread police 👮 for debug builds

[keyboardsurfer]

What I have done and why

App will now crash if someone does funky stuff on the main thread for debug builds.
This enforces programming thread safe programming (even though there are no obvious violations at the moment).
g
Do tests pass?

• Run local tests on DemoDebug variant: ./gradlew testDemoDebug
• Check formatting: ./gradlew --init-script gradle/init.gradle.kts spotlessApply

Is this your first pull request?

• Sign the CLA
• Run ./tools/setup.sh
• Import the code formatting style as explained in the setup script.

[lihenggui]

After enabling the StrictMode, the application will crash when launched.
Looks like there are some tasks remaining that need to be completed.

Process: com.google.samples.apps.nowinandroid.demo.debug, PID: 5363
java.lang.RuntimeException: StrictMode ThreadPolicy violation
	at android.os.StrictMode$AndroidBlockGuardPolicy.onThreadPolicyViolation(StrictMode.java:1883)
	at android.os.StrictMode$AndroidBlockGuardPolicy.lambda$handleViolationWithTimingAttempt$0(StrictMode.java:1797)
	at android.os.StrictMode$AndroidBlockGuardPolicy.$r8$lambda$AF9hglpXLeeg2_1ZxHCfZb2exEY(Unknown Source:0)
	at android.os.StrictMode$AndroidBlockGuardPolicy$$ExternalSyntheticLambda1.run(Unknown Source:6)
	at android.os.Handler.handleCallback(Handler.java:958)
	at android.os.Handler.dispatchMessage(Handler.java:99)
	at android.os.Looper.loopOnce(Looper.java:205)
	at android.os.Looper.loop(Looper.java:294)
	at android.app.ActivityThread.main(ActivityThread.java:8176)
	at java.lang.reflect.Method.invoke(Native Method)
	at com.android.internal.os.RuntimeInit$MethodAndArgsCaller.run(RuntimeInit.java:552)
	at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:971)
Caused by: android.os.strictmode.DiskReadViolation
	at android.os.StrictMode$AndroidBlockGuardPolicy.onReadFromDisk(StrictMode.java:1666)
	at libcore.io.BlockGuardOs.access(BlockGuardOs.java:74)
	at libcore.io.ForwardingOs.access(ForwardingOs.java:128)
	at android.app.ActivityThread$AndroidOs.access(ActivityThread.java:8053)
	at java.io.UnixFileSystem.checkAccess(UnixFileSystem.java:313)
	at java.io.File.exists(File.java:813)
	at android.app.ContextImpl.ensurePrivateDirExists(ContextImpl.java:790)
	at android.app.ContextImpl.ensurePrivateDirExists(ContextImpl.java:781)
	at android.app.ContextImpl.getPreferencesDir(ContextImpl.java:737)
	at android.app.ContextImpl.getSharedPreferencesPath(ContextImpl.java:962)
	at android.app.ContextImpl.getSharedPreferences(ContextImpl.java:583)
	at android.content.ContextWrapper.getSharedPreferences(ContextWrapper.java:221)
	at com.google.firebase.remoteconfig.RemoteConfigComponent.getMetadataClient(RemoteConfigComponent.java:299)
	at com.google.firebase.remoteconfig.RemoteConfigComponent.get(RemoteConfigComponent.java:162)
	at com.google.firebase.perf.config.RemoteConfigManager.isFirebaseRemoteConfigAvailable(RemoteConfigManager.java:395)
	at com.google.firebase.perf.config.RemoteConfigManager.triggerRemoteConfigFetchIfNecessary(RemoteConfigManager.java:331)
	at com.google.firebase.perf.config.RemoteConfigManager.getRemoteConfigValue(RemoteConfigManager.java:295)
	at com.google.firebase.perf.config.RemoteConfigManager.getBoolean(RemoteConfigManager.java:207)
	at com.google.firebase.perf.config.ConfigResolver.getRemoteConfigBoolean(ConfigResolver.java:867)
	at com.google.firebase.perf.config.ConfigResolver.getIsExperimentTTIDEnabled(ConfigResolver.java:826)
	at com.google.firebase.perf.metrics.AppStartTrace.onActivityResumed(AppStartTrace.java:352)
	at android.app.Application.dispatchActivityResumed(Application.java:431)
	at android.app.Activity.dispatchActivityResumed(Activity.java:1483)
	at android.app.Activity.onResume(Activity.java:2065)
	at com.google.samples.apps.nowinandroid.MainActivity.onResume(MainActivity.kt:157)
	at android.app.Instrumentation.callActivityOnResume(Instrumentation.java:1603)
	at android.app.Activity.performResume(Activity.java:8743)
	at android.app.ActivityThread.performResumeActivity(ActivityThread.java:4951)
	at android.app.ActivityThread.handleResumeActivity(ActivityThread.java:4994)
	at android.app.servertransaction.ResumeActivityItem.execute(ResumeActivityItem.java:57)
	at android.app.servertransaction.ActivityTransactionItem.execute(ActivityTransactionItem.java:45)
	at android.app.servertransaction.TransactionExecutor.executeLifecycleState(TransactionExecutor.java:180)
	at android.app.servertransaction.TransactionExecutor.execute(TransactionExecutor.java:98)
	at android.app.ActivityThread$H.handleMessage(ActivityThread.java:2443)
	at android.os.Handler.dispatchMessage(Handler.java:106)

[SimonMarquis]

Quick question: should we also enable strict VmPolicy?

[keyboardsurfer]

The RemoteConfig issue is being tracked here: firebase/firebase-android-sdk#5347 and I'm following up with the team.

[github-actions]

Combined test coverage report

Overall Project	42.32% -0.03%	🍏
Files changed	0%	❌

Module	Coverage
app	48.05% -0.24%	❌

Files

Module	File	Coverage
app	NiaApplication.kt	0% -27.27%	❌

[keyboardsurfer]

This PR does not break runtime any longer and can be accepted after positive review.

[dturner]

Minor refactoring required

[keyboardsurfer]

All requested changes addressed

[dturner]

It's.....beautiful.... 😍

[SimonMarquis]

FYI: the issue firebase/firebase-android-sdk#5347 has been closed and "locked and limited conversation to collaborators" while it seems to not be entirely fixed:

• [Bug]: crash app #1788 (comment)

@keyboardsurfer any idea what was fixed exactly on their side?

(I'm not able to reproduce the issue, though I don't have a similar device)

[keyboardsurfer]

I have no insights to share but the last comment on the issue shows where we can expect this to work firebase/firebase-android-sdk#5347 (comment)

[klemensz]

The crash still happens with the latest main branch. I also tried it with the latest Firebase BOM 33.10.0.