Fix ANRs when receiving push notifications (#6696)

In Sentry there are some reports of methods called when notifications are fetched that end up having ANRs. This looked weird because everything is asynchronous... but it's still running with a `Main` dispatcher.

Using the `Default/computation` one instead should be the right call.

libraries/push/impl/src/main/kotlin/io/element/android/libraries/push/impl/push/DefaultPushHandler.kt

@@ -11,6 +11,7 @@ package io.element.android.libraries.push.impl.push
 import dev.zacsweers.metro.AppScope
 import dev.zacsweers.metro.ContributesBinding
 import dev.zacsweers.metro.SingleIn
+import io.element.android.libraries.core.coroutine.CoroutineDispatchers
 import io.element.android.libraries.core.log.logger.LoggerTag
 import io.element.android.libraries.core.meta.BuildMeta
 import io.element.android.libraries.push.impl.db.PushRequest
@@ -35,6 +36,7 @@ import kotlinx.coroutines.CoroutineScope
 import kotlinx.coroutines.currentCoroutineContext
 import kotlinx.coroutines.flow.first
 import kotlinx.coroutines.launch
+import kotlinx.coroutines.withContext
 import timber.log.Timber
 
 private val loggerTag = LoggerTag("PushHandler", LoggerTag.PushLoggerTag)
@@ -53,6 +55,7 @@ class DefaultPushHandler(
     private val workManagerScheduler: WorkManagerScheduler,
     private val syncPendingNotificationsRequestFactory: SyncPendingNotificationsRequestBuilder.Factory,
     resultProcessor: NotificationResultProcessor,
+    private val dispatchers: CoroutineDispatchers,
 ) : PushHandler {
     init {
         resultProcessor.start()
@@ -64,7 +67,7 @@ class DefaultPushHandler(
      * @param pushData the data received in the push.
      * @param providerInfo the provider info.
      */
-    override suspend fun handle(pushData: PushData, providerInfo: String): Boolean {
+    override suspend fun handle(pushData: PushData, providerInfo: String): Boolean = withContext(dispatchers.computation) {
         // Start measuring how long it takes to display a notification from when the push is received
         Timber.d("Calculating push-to-notification for event ${pushData.eventId}")
         val parent = analyticsService.startLongRunningTransaction(AnalyticsLongRunningTransaction.PushToNotification(pushData.eventId.value))
@@ -81,7 +84,7 @@ class DefaultPushHandler(
         }
 
         // Diagnostic Push
-        return if (pushData.eventId == DefaultTestPush.TEST_EVENT_ID) {
+        if (pushData.eventId == DefaultTestPush.TEST_EVENT_ID) {
             pushHistoryService.onDiagnosticPush(providerInfo)
             diagnosticPushHandler.handlePush()
             false
@@ -90,7 +93,7 @@ class DefaultPushHandler(
         }
     }
 
-    override suspend fun handleInvalid(providerInfo: String, data: String) {
+    override suspend fun handleInvalid(providerInfo: String, data: String) = withContext(dispatchers.computation) {
         incrementPushDataStore.incrementPushCounter()
         pushHistoryService.onInvalidPushReceived(providerInfo, data)
     }

libraries/push/impl/src/test/kotlin/io/element/android/libraries/push/impl/push/DefaultPushHandlerTest.kt

@@ -11,6 +11,7 @@
 package io.element.android.libraries.push.impl.push
 
 import app.cash.turbine.test
+import io.element.android.libraries.core.coroutine.CoroutineDispatchers
 import io.element.android.libraries.core.meta.BuildMeta
 import io.element.android.libraries.matrix.api.core.EventId
 import io.element.android.libraries.matrix.api.core.RoomId
@@ -40,7 +41,9 @@ import io.element.android.services.toolbox.test.systemclock.FakeSystemClock
 import io.element.android.tests.testutils.lambda.lambdaError
 import io.element.android.tests.testutils.lambda.lambdaRecorder
 import io.element.android.tests.testutils.lambda.value
+import io.element.android.tests.testutils.testCoroutineDispatchers
 import kotlinx.coroutines.ExperimentalCoroutinesApi
+import kotlinx.coroutines.test.TestScope
 import kotlinx.coroutines.test.advanceTimeBy
 import kotlinx.coroutines.test.runCurrent
 import kotlinx.coroutines.test.runTest
@@ -212,7 +215,7 @@ class DefaultPushHandlerTest {
             .isCalledOnce()
     }
 
-    private fun createDefaultPushHandler(
+    private fun TestScope.createDefaultPushHandler(
         incrementPushCounterResult: () -> Unit = { lambdaError() },
         userPushStore: FakeUserPushStore = FakeUserPushStore(),
         pushClientSecret: PushClientSecret = FakePushClientSecret(),
@@ -227,6 +230,7 @@ class DefaultPushHandlerTest {
             start = {},
             stop = {},
         ),
+        dispatchers: CoroutineDispatchers = testCoroutineDispatchers(),
     ): DefaultPushHandler {
         return DefaultPushHandler(
             incrementPushDataStore = object : IncrementPushDataStore {
@@ -246,7 +250,8 @@ class DefaultPushHandlerTest {
             resultProcessor = resultProcessor,
             syncPendingNotificationsRequestFactory = SyncPendingNotificationsRequestBuilder.Factory {
                 FakeSyncPendingNotificationsRequestBuilder()
-            }
+            },
+            dispatchers = dispatchers,
         )
     }
 }