Migrate boxWithJava tests to multi-file framework

compiler/testData/codegen/boxWithJava/builtinStubMethods/substitutedIterable.kt

@@ -0,0 +1,28 @@
+// FILE: Test.java
+
+public class Test {
+    public static void checkCallFromJava() {
+        try {
+            String x = TestKt.foo().iterator().next();
+            throw new AssertionError("E should have been thrown");
+        } catch (E e) { }
+    }
+}
+
+// FILE: test.kt
+
+interface MyIterable<T> : Iterable<T>
+
+class E : RuntimeException()
+fun foo(): MyIterable<String> = throw E()
+
+fun box(): String {
+    try {
+        foo().iterator().next()
+        return "Fail: E should have been thrown"
+    } catch (e: E) {}
+
+    Test.checkCallFromJava()
+
+    return "OK"
+}