Move superinterface to the only subclass of FunctionBase

libraries/stdlib/jvm/runtime/kotlin/jvm/internal/FunctionBase.java

@@ -7,8 +7,6 @@ package kotlin.jvm.internal;
 
 import kotlin.Function;
 
-import java.io.Serializable;
-
-public interface FunctionBase extends Function, Serializable {
+public interface FunctionBase extends Function {
     int getArity();
 }

libraries/stdlib/jvm/runtime/kotlin/jvm/internal/Lambda.kt

@@ -5,8 +5,10 @@
 
 package kotlin.jvm.internal
 
-public abstract class Lambda(private val arity: Int) : FunctionBase {
-    override fun getArity() = arity
+import java.io.Serializable
 
-    override fun toString() = Reflection.renderLambdaToString(this)
+abstract class Lambda(private val arity: Int) : FunctionBase, Serializable {
+    override fun getArity(): Int = arity
+
+    override fun toString(): String = Reflection.renderLambdaToString(this)
 }

libraries/tools/binary-compatibility-validator/reference-public-api/kotlin-runtime.txt

@@ -507,7 +507,7 @@ public final class kotlin/jvm/internal/FloatSpreadBuilder : kotlin/jvm/internal/
 	public final fun toArray ()[F
 }
 
-public abstract interface class kotlin/jvm/internal/FunctionBase : java/io/Serializable, kotlin/Function {
+public abstract interface class kotlin/jvm/internal/FunctionBase : kotlin/Function {
 	public abstract fun getArity ()I
 }
 
@@ -630,7 +630,7 @@ public class kotlin/jvm/internal/Intrinsics {
 	public static fun throwUninitializedPropertyAccessException (Ljava/lang/String;)V
 }
 
-public abstract class kotlin/jvm/internal/Lambda : kotlin/jvm/internal/FunctionBase {
+public abstract class kotlin/jvm/internal/Lambda : java/io/Serializable, kotlin/jvm/internal/FunctionBase {
 	public fun <init> (I)V
 	public fun getArity ()I
 	public fun toString ()Ljava/lang/String;

libraries/tools/binary-compatibility-validator/reference-public-api/kotlin-stdlib-runtime-merged.txt

@@ -3329,7 +3329,7 @@ public final class kotlin/jvm/internal/FloatSpreadBuilder : kotlin/jvm/internal/
 	public final fun toArray ()[F
 }
 
-public abstract interface class kotlin/jvm/internal/FunctionBase : java/io/Serializable, kotlin/Function {
+public abstract interface class kotlin/jvm/internal/FunctionBase : kotlin/Function {
 	public abstract fun getArity ()I
 }
 
@@ -3452,7 +3452,7 @@ public class kotlin/jvm/internal/Intrinsics {
 	public static fun throwUninitializedPropertyAccessException (Ljava/lang/String;)V
 }
 
-public abstract class kotlin/jvm/internal/Lambda : kotlin/jvm/internal/FunctionBase {
+public abstract class kotlin/jvm/internal/Lambda : java/io/Serializable, kotlin/jvm/internal/FunctionBase {
 	public fun <init> (I)V
 	public fun getArity ()I
 	public fun toString ()Ljava/lang/String;