Minor in JS backend: added regression tests.

#{KT-2219, KT-2470, KT-2507, KT-2222, KT-2995, KT-2221} Obsolete

js/js.translator/testData/regression/cases/kt2470.kt

@@ -0,0 +1,24 @@
+// KT-2470 another name mangling bug: kotlin.test.failsWith() gets generated to invalid JS
+
+package foo
+
+native val Exception.message: String = noImpl
+
+public fun <T : Throwable> failsWith(block: () -> Any): T {
+    try {
+        block()
+    }
+    catch (e: T) {
+        return e
+    }
+
+    throw Exception("Should have failed")
+}
+
+fun box(): String {
+    val a = failsWith<Exception> {
+        throw Exception("OK")
+    }
+
+    return a.message
+}