Migrate boxInline tests to new multi-file framework

compiler/testData/codegen/boxInline/syntheticAccessors/propertyModifiers.kt

@@ -0,0 +1,38 @@
+// FILE: 1.kt
+
+package test
+
+class P {
+    private val FOO_PRIVATE = "OK"
+
+    final val FOO_FINAL = "OK"
+
+    private inline fun fooPrivate(): String {
+        return FOO_PRIVATE
+    }
+
+    private inline fun fooFinal(): String {
+        return FOO_FINAL
+    }
+
+    fun testPrivate(): String {
+        return fooPrivate()
+    }
+
+    fun testFinal(): String {
+        return fooFinal()
+    }
+}
+
+// FILE: 2.kt
+
+import test.*
+
+fun box() : String {
+    val p = P()
+
+    if (p.testPrivate() != "OK") return "fail 1 ${p.testPrivate()}"
+
+    if (p.testFinal() != "OK") return "fail 2 ${p.testFinal()}"
+    return "OK"
+}