Don't create NamespaceType for enum entries

Enum entry expressions have the type of their enum, so it shouldn't be possible
to access static nested classes of enum entries from outside.

This fixes BlackBoxCodegenTestGenerated$CallableReference.testEnumNameMethod

compiler/tests/org/jetbrains/jet/checkers/JetDiagnosticsTestGenerated.java

@@ -2532,6 +2532,11 @@ public class JetDiagnosticsTestGenerated extends AbstractDiagnosticsTestWithEage
                 JetTestUtils.assertAllTestsPresentByMetadata(this.getClass(), "org.jetbrains.jet.generators.tests.GenerateTests", new File("compiler/testData/diagnostics/tests/enum"), Pattern.compile("^(.+)\\.kt$"), true);
             }
             
+            @TestMetadata("dontCreateNamespaceTypeForEnumEntry.kt")
+            public void testDontCreateNamespaceTypeForEnumEntry() throws Exception {
+                doTest("compiler/testData/diagnostics/tests/enum/dontCreateNamespaceTypeForEnumEntry.kt");
+            }
+            
             @TestMetadata("entryShouldBeOfEnumType.kt")
             public void testEntryShouldBeOfEnumType() throws Exception {
                 doTest("compiler/testData/diagnostics/tests/enum/entryShouldBeOfEnumType.kt");