[FIR] Add workaround for KT-19306

compiler/fir/cones/src/org/jetbrains/kotlin/fir/types/ConeAttributes.kt

@@ -6,6 +6,7 @@
 package org.jetbrains.kotlin.fir.types
 
 import org.jetbrains.kotlin.fir.utils.AttributeArrayOwner
+import org.jetbrains.kotlin.fir.utils.Protected
 import org.jetbrains.kotlin.fir.utils.TypeRegistry
 import org.jetbrains.kotlin.fir.utils.isEmpty
 import org.jetbrains.kotlin.utils.addIfNotNull
@@ -20,6 +21,7 @@ abstract class ConeAttribute<T : ConeAttribute<T>> {
     abstract val key: KClass<out T>
 }
 
+@OptIn(Protected::class)
 class ConeAttributes private constructor(attributes: List<ConeAttribute<*>>) : AttributeArrayOwner<ConeAttribute<*>, ConeAttribute<*>>() {
     companion object : TypeRegistry<ConeAttribute<*>, ConeAttribute<*>>() {
         inline fun <reified T : ConeAttribute<T>> attributeAccessor(): ReadOnlyProperty<ConeAttributes, T?> {

compiler/fir/cones/src/org/jetbrains/kotlin/fir/utils/ArrayMapOwner.kt

@@ -10,8 +10,14 @@ import kotlin.properties.ReadOnlyProperty
 import kotlin.reflect.KClass
 import kotlin.reflect.KProperty
 
+@RequiresOptIn
+annotation class Protected
+
+@OptIn(Protected::class)
 abstract class AbstractArrayMapOwner<K : Any, V : Any> {
-    protected abstract val arrayMap: ArrayMap<V>
+    // TODO: make [arrayMap] protected and remove annotation after KT-19306 fix
+    @get:Protected
+    abstract val arrayMap: ArrayMap<V>
     protected abstract val typeRegistry: TypeRegistry<K, V>
 
     abstract class AbstractArrayMapAccessor<K : Any, V : Any, T : V>(

compiler/fir/cones/src/org/jetbrains/kotlin/fir/utils/AttributeArrayOwner.kt

@@ -16,6 +16,7 @@ import kotlin.reflect.KClass
  * Note that you can remove attributes from [AttributeArrayOwner] despite
  *   from components in [ComponentArrayOwner]
  */
+@OptIn(Protected::class)
 abstract class AttributeArrayOwner<K : Any, T : Any> : AbstractArrayMapOwner<K, T>() {
     @Suppress("UNCHECKED_CAST")
     final override var arrayMap: ArrayMap<T> = EmptyArrayMap as ArrayMap<T>

compiler/fir/cones/src/org/jetbrains/kotlin/fir/utils/ComponentArrayOwner.kt

@@ -11,6 +11,7 @@ import kotlin.reflect.KClass
  * [ComponentArrayOwner] based on [ArrayMap] with flexible size and should be used for
  *   storing services in entities with limited number of instances, like FirSession
  */
+@OptIn(Protected::class)
 abstract class ComponentArrayOwner<K : Any, V : Any> : AbstractArrayMapOwner<K, V>() {
     final override val arrayMap: ArrayMap<V> =
         ArrayMapImpl()

compiler/fir/resolve/src/org/jetbrains/kotlin/fir/extensions/FirExtensionService.kt

@@ -9,6 +9,7 @@ import org.jetbrains.kotlin.fir.FirSession
 import org.jetbrains.kotlin.fir.FirSessionComponent
 import org.jetbrains.kotlin.fir.utils.ArrayMapAccessor
 import org.jetbrains.kotlin.fir.utils.ComponentArrayOwner
+import org.jetbrains.kotlin.fir.utils.Protected
 import org.jetbrains.kotlin.fir.utils.TypeRegistry
 import kotlin.reflect.KClass
 
@@ -47,6 +48,7 @@ class FirExtensionService(val session: FirSession) : ComponentArrayOwner<FirExte
     }
 
     @PluginServicesInitialization
+    @OptIn(Protected::class)
     fun getAllExtensions(): List<FirExtension> {
         return arrayMap.flatten()
     }