[bendk]

#7636 broke the app-services-error-reporter tracing event fields by renaming breadcrumbs to breadcrumb_string. This caused crashes on Android when errors were reported.

Rename it back to breadcrumbs and add a test so that this doesn't happen again.

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[AaronMT]

Stack where I saw this crash on auto-land (10/14) off a robo-crawl https://treeherder.mozilla.org/jobs?repo=autoland&revision=8c09abb17fd98be2828cefbcad9d0896087a7645&selectedTaskRun=fRJkrtcWQZKQ9iRjEoQ6dg.0

https://firefoxci.taskcluster-artifacts.net/a2Ek2JlETByh5kT0OLgR0Q/0/public/results/data_app_crash_0_org_mozilla_fenix_debug.txt

mozilla.appservices.fxaclient.InternalException: Callback interface failure: UnexpectedUniFFICallbackError(reason: "kotlinx.serialization.MissingFieldException: Field 'breadcrumbs' is required for type with serial name 'mozilla.appservices.errorsupport.TracingErrorFields', but it was missing at path: $
	at kotlinx.serialization.internal.JsonInternalDependenciesKt.missingFieldExceptionWithNewMessage(JsonInternalDependencies.kt:21)
	at kotlinx.serialization.json.internal.StreamingJsonDecoder.decodeSerializableValue(StreamingJsonDecoder.kt:95)
	at kotlinx.serialization.json.Json.decodeFromString(Json.kt:149)
	at mozilla.appservices.errorsupport.ErrorEventSink.onEvent(RustComponentsErrorTelemetry.kt:74)
	at mozilla.appservices.tracing.uniffiCallbackInterfaceEventSink$onEvent.callback$lambda$0(tracing.kt:1230)
	at mozilla.appservices.tracing.uniffiCallbackInterfaceEventSink$onEvent$$ExternalSyntheticLambda0.invoke(D8$$SyntheticClass:0)
	at mozilla.appservices.tracing.uniffiCallbackInterfaceEventSink$onEvent.callback(tracing.kt:1365)
	at java.lang.reflect.Method.invoke(Native Method)
	at com.sun.jna.CallbackReference$DefaultCallbackProxy.invokeCallback(CallbackReference.java:585)
	at com.sun.jna.CallbackReference$DefaultCallbackProxy.callback(CallbackReference.java:613)
	at mozilla.appservices.fxaclient.UniffiLib.uniffi_fxa_client_fn_method_firefoxaccount_process_event(Native Method)
	at mozilla.appservices.fxaclient.FirefoxAccount.processEvent(fxa_client.kt:2332)
	at mozilla.appservices.fxaclient.FxaClient.processEvent(FxaClient.kt:96)
	at mozilla.components.service.fxa.FirefoxAccount.processEvent$service_firefox_accounts(FirefoxAccount.kt:96)
	at mozilla.components.service.fxa.manager.FxaAccountManager.processQueue(FxaAccountManager.kt:478)
	at mozilla.components.service.fxa.manager.FxaAccountManager.access$processQueue(FxaAccountManager.kt:98)
	at mozilla.components.service.fxa.manager.FxaAccountManager$beginAuthentication$2.invokeSuspend(FxaAccountManager.kt:376)
	at kotlin.coroutines.jvm.internal.BaseContinuationImpl.resumeWith(ContinuationImpl.kt:34)
	at kotlinx.coroutines.DispatchedTask.run(DispatchedTask.kt:100)
	at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1154)
	at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:652)
	at java.lang.Thread.run(Thread.java:1563)
")
	at mozilla.appservices.fxaclient.Fxa_clientKt.uniffiCheckCallStatus(fxa_client.kt:291)
	at mozilla.appservices.fxaclient.Fxa_clientKt.access$uniffiCheckCallStatus(fxa_client.kt:1)
	at mozilla.appservices.fxaclient.FirefoxAccount.processEvent(fxa_client.kt:5881)
	at mozilla.appservices.fxaclient.FxaClient.processEvent(FxaClient.kt:96)
	at mozilla.components.service.fxa.FirefoxAccount.processEvent$service_firefox_accounts(FirefoxAccount.kt:96)
	at mozilla.components.service.fxa.manager.FxaAccountManager.processQueue(FxaAccountManager.kt:478)
	at mozilla.components.service.fxa.manager.FxaAccountManager.access$processQueue(FxaAccountManager.kt:98)
	at mozilla.components.service.fxa.manager.FxaAccountManager$beginAuthentication$2.invokeSuspend(FxaAccountManager.kt:376)
	at kotlin.coroutines.jvm.internal.BaseContinuationImpl.resumeWith(ContinuationImpl.kt:34)
	at kotlinx.coroutines.DispatchedTask.run(DispatchedTask.kt:100)
	at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1154)
	at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:652)
	at java.lang.Thread.run(Thread.java:1563)
	Suppressed: kotlinx.coroutines.internal.DiagnosticCoroutineContextException: [StandaloneCoroutine{Cancelling}@6f19d62, Dispatchers.IO]