KT-449 class object in inner class must be an error

===
class A {
  class B {
    class object { }
  }
}
===

compiler/testData/checkerWithErrorTypes/quick/InnerClassClassObject.jet

@@ -0,0 +1,7 @@
+// http://youtrack.jetbrains.net/issue/KT-449
+
+class A {
+    class B {
+        <!CLASS_OBJECT_NOT_ALLOWED!>class object { }<!>
+    }
+}