[FIR JS] Prepare the test data for FIR

compiler/testData/diagnostics/testsWithJsStdLib/export/jsExportOnNestedDeclarations.fir.kt

@@ -0,0 +1,22 @@
+// !OPT_IN: kotlin.js.ExperimentalJsExport
+
+package foo
+
+class C1 {
+    @JsExport
+    fun f1() {}
+
+    @JsExport
+    val p: Int = 10
+
+    @JsExport
+    object O
+}
+
+fun f2() {
+    @JsExport
+    fun f3() {}
+
+    @JsExport
+    class C2
+}