Support annotations on type aliases declarations

compiler/serialization/src/org/jetbrains/kotlin/serialization/DescriptorSerializer.kt

@@ -306,6 +306,8 @@ class DescriptorSerializer private constructor(
             builder.setExpandedType(local.type(expandedType))
         }
 
+        builder.addAllAnnotation(descriptor.annotations.map { extension.annotationSerializer.serializeAnnotation(it) })
+
         return builder
     }
 

compiler/serialization/src/org/jetbrains/kotlin/serialization/SerializerExtension.kt

@@ -23,6 +23,8 @@ import org.jetbrains.kotlin.types.KotlinType
 abstract class SerializerExtension {
     abstract val stringTable: StringTable
 
+    val annotationSerializer by lazy { AnnotationSerializer(stringTable) }
+
     open fun shouldUseTypeTable(): Boolean = false
 
     open fun serializeClass(descriptor: ClassDescriptor, proto: ProtoBuf.Class.Builder) {

compiler/serialization/src/org/jetbrains/kotlin/serialization/SerializerExtensionBase.kt

@@ -22,7 +22,6 @@ import org.jetbrains.kotlin.types.KotlinType
 
 open class KotlinSerializerExtensionBase(private val protocol: SerializerExtensionProtocol) : SerializerExtension() {
     override final val stringTable = StringTableImpl()
-    private val annotationSerializer = AnnotationSerializer(stringTable)
 
     override fun serializeClass(descriptor: ClassDescriptor, proto: ProtoBuf.Class.Builder) {
         for (annotation in descriptor.annotations) {