JS frontend: added tests for nativeInvoke, nativeGetter, nativeSetter.

compiler/testData/diagnostics/testsWithJsStdLib/native/nativeGetter/onLocalExtensionFun.kt

@@ -0,0 +1,21 @@
+// !DIAGNOSTICS: -UNUSED_PARAMETER
+
+fun foo() {
+    [nativeGetter]
+    fun Int.get(a: String): Int? = 1
+
+    [nativeGetter]
+    fun Int.get2(a: Number): String? = "OK"
+
+    [nativeGetter]
+    fun Int.get3(a: Int): String? = "OK"
+
+    [nativeGetter]
+    fun Int.get(<!NATIVE_INDEXER_KEY_SHOULD_BE_STRING_OR_NUMBER!>a: Any<!>): Int? = 1
+
+    <!NATIVE_INDEXER_WRONG_PARAMETER_COUNT!>[nativeGetter]
+    fun Int.get2(): String?<!> = "OK"
+
+    <!NATIVE_INDEXER_WRONG_PARAMETER_COUNT!>[nativeGetter]
+    fun Int.get3(<!NATIVE_INDEXER_KEY_SHOULD_BE_STRING_OR_NUMBER!>a: Any<!>, b: Int, c: Any?): String?<!> = "OK"
+}