Preliminary implementation of parts & facade in FIR-based compiler

core/deserialization/src/org/jetbrains/kotlin/serialization/deserialization/descriptors/DeserializedMemberDescriptor.kt

@@ -16,7 +16,11 @@ import org.jetbrains.kotlin.serialization.deserialization.IncompatibleVersionErr
 import org.jetbrains.kotlin.storage.StorageManager
 import org.jetbrains.kotlin.types.*
 
-interface DeserializedMemberDescriptor : MemberDescriptor {
+interface DescriptorWithContainerSource : MemberDescriptor {
+    val containerSource: DeserializedContainerSource?
+}
+
+interface DeserializedMemberDescriptor : MemberDescriptor, DescriptorWithContainerSource {
     val proto: MessageLite
 
     val nameResolver: NameResolver
@@ -30,7 +34,7 @@ interface DeserializedMemberDescriptor : MemberDescriptor {
 
     // Information about the origin of this callable's container (class or package part on JVM) or null if there's no such information.
     // TODO: merge with sourceElement of containingDeclaration
-    val containerSource: DeserializedContainerSource?
+    override val containerSource: DeserializedContainerSource?
 
     val coroutinesExperimentalCompatibilityMode: CoroutinesCompatibilityMode