IssueTracker

Updated description: The ability to use background threads to should help us prevent ANRs caused by AndroidX MediaRouter work.

Original description:

Component used: media router Version used: Master from Androidx Devices/Android versions reproduced on: Any

MediaRouter must be initialized in main thread, it will then create GlobalMediaRouter on main thread leading to RegisteredMediaRouteProviderWatcher having it's handler tied to main thread.

And then the issue starts since the scans use package manager that use binder and is slow and should not be called on main thread. The scans should be made in background that does not prevent the callbacks from then being called on main thread.

The ANR:

#00 pc 0x99000 libc.so (syscall + 32) (BuildId: f5f7a5dceb6ab17a1a448521eb52ce18)
#01 pc 0x23247c libart.so (art::ConditionVariable::WaitHoldingLocks + 140) (BuildId: ddcc440d4609d2099db9d20895487a78)
#02 pc 0x45b218 libart.so (artJniMethodEnd + 336) (BuildId: ddcc440d4609d2099db9d20895487a78)
#03 pc 0x5bf0fc libart.so (art_jni_method_end + 12) (BuildId: ddcc440d4609d2099db9d20895487a78)
       at android.os.BinderProxy.transactNative(Native method)
       at android.os.BinderProxy.transact(BinderProxy.java:685)
       at android.content.pm.IPackageManager$Stub$Proxy.queryIntentServices(IPackageManager.java:5022)
       at android.app.ApplicationPackageManager.queryIntentServicesAsUser(ApplicationPackageManager.java:1657)
       at android.app.ApplicationPackageManager.queryIntentServices(ApplicationPackageManager.java:1678)
       at android.app.ApplicationPackageManager.queryIntentServices(ApplicationPackageManager.java:1673)
       at androidx.mediarouter.media.RegisteredMediaRouteProviderWatcher.getMediaRoute2ProviderServices(RegisteredMediaRouteProviderWatcher.java:173)
       at androidx.mediarouter.media.RegisteredMediaRouteProviderWatcher.scanPackages(RegisteredMediaRouteProviderWatcher.java:107)
       at androidx.mediarouter.media.RegisteredMediaRouteProviderWatcher$1.onReceive(RegisteredMediaRouteProviderWatcher.java:193)
       at android.app.LoadedApk$ReceiverDispatcher$Args.lambda$getRunnable$0(LoadedApk.java:1943)
       at android.app.LoadedApk$ReceiverDispatcher$Args.$r8$lambda$gDuJqgxY6Zb-ifyeubKeivTLAwk(unavailable)
       at android.app.LoadedApk$ReceiverDispatcher$Args$$ExternalSyntheticLambda0.run(unavailable:2)
       at android.os.Handler.handleCallback(Handler.java:958)
       at android.os.Handler.dispatchMessage(Handler.java:99)
       at android.os.Looper.loopOnce(Looper.java:257)
       at android.os.Looper.loop(Looper.java:368)
       at android.app.ActivityThread.main(ActivityThread.java:8848)
       at java.lang.reflect.Method.invoke(Native method)
       at com.android.internal.os.RuntimeInit$MethodAndArgsCaller.run(RuntimeInit.java:572)
       at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:1049)