Migrate boxInline tests to new multi-file framework

compiler/testData/codegen/boxInline/reified/kt7017.kt

@@ -0,0 +1,23 @@
+// FILE: 1.kt
+
+package test
+
+inline fun <reified T> test(x: Any): Boolean {
+    val x = object {
+        val y = x is T
+    }
+
+    return x.y
+}
+
+// FILE: 2.kt
+
+import test.*
+
+fun box(): String {
+    if (!test<String>("OK")) return "fail 1"
+
+    if (test<Int>("OK")) return "fail 2"
+
+    return "OK"
+}