Migrate boxAgainstJava tests to multi-file framework

compiler/testData/codegen/boxAgainstJava/delegation/delegationAndInheritanceFromJava.kt

@@ -1,4 +1,16 @@
-import delegationAndInheritanceFromJava.*
+// FILE: Foo.java
+
+import java.util.Set;
+
+public class Foo {
+    public interface A extends Set<String> {}
+
+    public interface B extends Set<String> {}
+}
+
+// FILE: 1.kt
+
+import Foo.*
 import java.util.HashSet
 
 class Impl(b: B): A, B by b