Crash in new schema attempting to delete unused media when doing a media check

[mikehardy]

Took a crash attempting to delete unused media when doing a media check on a pretty trashy collection - shouldn't crash ever but what's the best way to handle it? Perhaps just show an info that deletion failed because system threw error %s ?

I/System.out( 6213): localized: "IoError(\"Os { code: 1, kind: PermissionDenied, message: \\\"Operation not permitted\\\" }\")"
I/System.out( 6213): kind: IO_ERROR
D/UsageAnalytics( 6213): sendAnalyticsException() description/fatal: net.ankiweb.rsdroid.exceptions.BackendIoException: IoError("Os { code: 1, kind: PermissionDenied, message: \"Operation not permitted\" }")/true
I/ACRA    ( 6213): ACRA is disabled for com.ichi2.anki - forwarding uncaught Exception on to default ExceptionHandler
--------- beginning of crash
E/AndroidRuntime( 6213): FATAL EXCEPTION: AsyncTask #3
E/AndroidRuntime( 6213): Process: com.ichi2.anki, PID: 6213
E/AndroidRuntime( 6213): java.lang.RuntimeException: An error occured while executing doInBackground()
E/AndroidRuntime( 6213): 	at android.os.AsyncTask$3.done(AsyncTask.java:300)
E/AndroidRuntime( 6213): 	at java.util.concurrent.FutureTask.finishCompletion(FutureTask.java:355)
E/AndroidRuntime( 6213): 	at java.util.concurrent.FutureTask.setException(FutureTask.java:222)
E/AndroidRuntime( 6213): 	at java.util.concurrent.FutureTask.run(FutureTask.java:242)
E/AndroidRuntime( 6213): 	at android.os.AsyncTask$SerialExecutor$1.run(AsyncTask.java:231)
E/AndroidRuntime( 6213): 	at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1112)
E/AndroidRuntime( 6213): 	at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:587)
E/AndroidRuntime( 6213): 	at java.lang.Thread.run(Thread.java:818)
E/AndroidRuntime( 6213): Caused by: net.ankiweb.rsdroid.exceptions.BackendIoException: IoError("Os { code: 1, kind: PermissionDenied, message: \"Operation not permitted\" }")
E/AndroidRuntime( 6213): 	at net.ankiweb.rsdroid.BackendException$Companion.fromError(BackendException.kt:117)
E/AndroidRuntime( 6213): 	at net.ankiweb.rsdroid.BackendKt.unpackResult(Backend.kt:323)
E/AndroidRuntime( 6213): 	at net.ankiweb.rsdroid.BackendKt.access$unpackResult(Backend.kt:1)
E/AndroidRuntime( 6213): 	at net.ankiweb.rsdroid.Backend$runMethodRaw$1.invoke(Backend.kt:130)
E/AndroidRuntime( 6213): 	at net.ankiweb.rsdroid.Backend$runMethodRaw$1.invoke(Backend.kt:129)
E/AndroidRuntime( 6213): 	at net.ankiweb.rsdroid.Backend.withBackend(Backend.kt:157)
E/AndroidRuntime( 6213): 	at net.ankiweb.rsdroid.Backend.runMethodRaw(Backend.kt:129)
E/AndroidRuntime( 6213): 	at anki.backend.GeneratedBackend.trashMediaFilesRaw(GeneratedBackend.kt:3200)
E/AndroidRuntime( 6213): 	at anki.backend.GeneratedBackend.trashMediaFiles(GeneratedBackend.kt:3210)
E/AndroidRuntime( 6213): 	at com.ichi2.libanki.BackendMedia.removeFiles(BackendMedia.kt:59)
E/AndroidRuntime( 6213): 	at com.ichi2.async.CollectionTask$DeleteMedia.task(CollectionTask.kt:1124)
E/AndroidRuntime( 6213): 	at com.ichi2.async.CollectionTask$DeleteMedia.task(CollectionTask.kt:1119)
E/AndroidRuntime( 6213): 	at com.ichi2.async.TaskDelegate.execTask(TaskDelegate.kt:50)
E/AndroidRuntime( 6213): 	at com.ichi2.async.CollectionTask.actualDoInBackground(CollectionTask.kt:136)
E/AndroidRuntime( 6213): 	at com.ichi2.async.CollectionTask.doInBackground(CollectionTask.kt:98)
E/AndroidRuntime( 6213): 	at com.ichi2.async.CollectionTask.doInBackground(CollectionTask.kt:64)
E/AndroidRuntime( 6213): 	at android.os.AsyncTask$2.call(AsyncTask.java:288)
E/AndroidRuntime( 6213): 	at java.util.concurrent.FutureTask.run(FutureTask.java:237)
E/AndroidRuntime( 6213): 	... 4 more
W/ActivityManager( 1497):   Force finishing activity com.ichi2.anki/.DeckPicker
W/ActivityManager( 1497):   Force finishing activity com.android.documentsui/.DocumentsActivity

Originally posted by @mikehardy in #11849 (comment)

[mikehardy]

Confirmed fixed with the new commit on #11849 - thanks!