Enable d8 desugaring

app/build.gradle.kts

@@ -70,10 +70,15 @@ android {
     }
 
     compileOptions {
+        coreLibraryDesugaringEnabled = true
         sourceCompatibility = JavaVersion.VERSION_1_8
         targetCompatibility = JavaVersion.VERSION_1_8
     }
 
+    kotlinOptions {
+        jvmTarget = "1.8"
+    }
+
     @Suppress("LocalVariableName")
     buildTypes {
         getByName("debug") {
@@ -132,6 +137,7 @@ configurations.all {
 val googleplayImplementation by configurations
 
 dependencies {
+    coreLibraryDesugaring("com.android.tools:desugar_jdk_libs:1.0.5")
     implementation("com.gitlab.bitfireAT:dav4jvm:2.1")
     implementation("com.gitlab.bitfireAT:ical4android:1.0") {
         exclude(group = "org.threeten", module = "threetenbp")

app/src/main/java/org/tasks/data/TaskListQuery.kt

@@ -8,7 +8,7 @@ import com.todoroo.astrid.api.CaldavFilter
 import com.todoroo.astrid.api.Filter
 import com.todoroo.astrid.api.GtasksFilter
 import com.todoroo.astrid.data.Task
-import okhttp3.internal.immutableListOf
+import kotlinx.collections.immutable.persistentListOf
 import org.tasks.data.TaskListQueryNonRecursive.getNonRecursiveQuery
 import org.tasks.data.TaskListQueryRecursive.getRecursiveQuery
 import org.tasks.preferences.Preferences
@@ -26,7 +26,7 @@ object TaskListQuery {
         ${Join.left(Geofence.TABLE, Geofence.TASK.eq(Task.ID))}
         ${Join.left(Place.TABLE, Place.UID.eq(Geofence.PLACE))}
     """.trimIndent()
-    val FIELDS = immutableListOf(
+    val FIELDS = persistentListOf(
             field("tasks.*"),
             field("${TaskListFragment.GTASK_METADATA_JOIN}.*"),
             field("${TaskListFragment.CALDAV_METADATA_JOIN}.*"),