JS: add tests to prove that compiler does not optimize RTTI and safe calls based on type information. Remove corresponding optimization for !! operation. See KT-14033

js/js.translator/testData/box/expression/cast/explicitUpcast.js

@@ -0,0 +1,3 @@
+function createWrongObject() {
+    return new (JS_TESTS.foo.C);
+}

js/js.translator/testData/box/expression/cast/explicitUpcast.kt

@@ -0,0 +1,34 @@
+package foo
+
+open class A
+
+class B : A()
+
+class C
+
+fun box(): String {
+    var b: B = createWrongObject()
+    if (b is A) return "fail1: is"
+    if (b as? A != null) return "fail1: as?"
+    try {
+        println(b as A)
+        return "fail1: as"
+    }
+    catch (e: ClassCastException) {
+        // It's expected
+    }
+
+    b = B()
+    if (b !is A) return "fail2: is"
+    if (b as? A == null) return "fail2: as?"
+    try {
+        if ((b as A) != b) return "fail2: as"
+    }
+    catch (e: ClassCastException) {
+        return "fail2a: as"
+    }
+
+    return "OK"
+}
+
+external fun createWrongObject(): B