Add regression test for KT-2673

#KT-2673 Obsolete

compiler/testData/codegen/regressions/kt2673.kt

@@ -0,0 +1,8 @@
+fun box(): String {
+    enum class K {
+        O
+        K
+    }
+
+    return K.O.toString() + K.K.toString()
+}

compiler/tests/org/jetbrains/jet/codegen/EnumGenTest.java

@@ -171,4 +171,8 @@ public class EnumGenTest extends CodegenTestCase {
     public void testAbstractMethodInEnum() {
         blackBoxFile("enum/abstractMethodInEnum.kt");
     }
+
+    public void testKt2673() {
+        blackBoxFile("regressions/kt2673.kt");
+    }
 }