Kapt3: Write stub class files with metadata (needed for incremental compilation)

compiler/testData/codegen/light-analysis/localClasses/anonymousObjectInParameterInitializer.txt

@@ -1,3 +1,4 @@
+@kotlin.Metadata
 public final class A {
     private final @org.jetbrains.annotations.NotNull field a: java.lang.String
     public @synthetic.kotlin.jvm.GeneratedByJvmOverloads method <init>(): void
@@ -6,6 +7,7 @@ public final class A {
     public final @org.jetbrains.annotations.NotNull method getA(): java.lang.String
 }
 
+@kotlin.Metadata
 public final class AnonymousObjectInParameterInitializerKt {
     public final static @org.jetbrains.annotations.NotNull method box(): java.lang.String
 }