Simplistic support for native flag

compiler/testData/codegen/boxWithStdlib/native/simpleNative.kt

@@ -0,0 +1,15 @@
+import kotlin.jvm.*
+
+class WithNative {
+    native fun foo() {}
+}
+
+fun box(): String {
+    try {
+        WithNative().foo()
+        return "Link error expected"
+    }
+    catch (e: java.lang.UnsatisfiedLinkError) {
+        return "OK"
+    }
+}