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

compiler/testData/codegen/light-analysis/reflection/methodsFromAny/functionEqualsHashCode.txt

@@ -1,13 +1,16 @@
+@kotlin.Metadata
 public final class A {
     public method <init>(): void
     public final method mem(): void
 }
 
+@kotlin.Metadata
 public final class B {
     public method <init>(): void
     public final method mem(): void
 }
 
+@kotlin.Metadata
 public final class FunctionEqualsHashCodeKt {
     public final static @org.jetbrains.annotations.NotNull method box(): java.lang.String
     public final static method checkEqual(@org.jetbrains.annotations.NotNull p0: java.lang.Object, @org.jetbrains.annotations.NotNull p1: java.lang.Object): void